UD entomologist discusses stoneflies, official state macroinvertebrate

June 25, 2013 under CANR News
stoneflies

Frank Peairs, Colorado State University, Bugwood.org

On a recent morning, Ingrid Feustel and Ed Trommelen donned rubber boots, grabbed nets and collection buckets, and splashed their way into a tributary of the Red Clay Creek in search of stoneflies.

The duo are spending the summer conducting a macroinvertebrate survey as Stream Watch interns for the Delaware Nature Society.

As Feustel set out sampling jars, Trommelen kicked up pebbles with the toe of his boot, then dragged the net over the churned-up water. “I’ve got some stoneflies,” said Trommelen, after a glance inside the net.

Most people would probably only notice leaves, twigs and pebbles but Trommelen quickly identified the stoneflies, even though they’re itty-bitty (one-half to 1 1/2 inches long as adults and even smaller as juveniles.)

The interns collected stoneflies throughout the morning, making note of how many were in each sample, as well as any other macroinvertebrates — such as mayflies, caddisflies and worms — that they found. While it’s certainly fun to splash around a sun-dappled creek on a June day, why would the Delaware Nature Society care how many stoneflies are in local creeks?

“Stoneflies serve as the canary in the coal mine in terms of assessing the water quality of streams and creeks,” said Brian Kunkel, an entomologist with University of Delaware Cooperative Extension. “It makes sense to focus on stoneflies. Stoneflies need running water that contains lots of oxygen. Scientists can tell if a stream is polluted or not based on whether stoneflies are present.”

In fact, the stonefly is such an excellent indicator of water quality that it was chosen to be the official state macroinvertebrate. The May 4, 2005, proclamation that made it official says that the designation of the stonefly was a means “whereby Delaware state government could recognize the importance of excellent water quality and the vital role played by healthy aquatic ecosystems in Delaware.”

Delaware actually has three official insects – the lady bug, the tiger swallowtail (which is the state butterfly) and the stonefly. The distinguishing feature of a macroinvertebrate is that it doesn’t have a backbone.

Stoneflies aren’t just an indicator of pure water; they also help to keep it that way. Most species are herbivores; they eat decaying vegetation and algae, said Kunkel.

There are 38 known species of stoneflies that call Delaware home. Nineteen live exclusively in the Piedmont, in the northern one-fourth of New Castle County; eight live in the Coastal Plain, which makes up the other three-fourths of the state; and 11 can be found in both the Piedmont and the Coastal Plain.

Adult stoneflies are weak fliers and like to hang out on stones (hence their name) and also on logs. If they lose their grip and fall into the water they may get eaten by trout, which prefer mayflies but will eat stoneflies if that’s the only food around.

Even if it doesn’t become dinner for a trout, an adult stonefly only lives about three to four weeks. Nymphs, on the other hand, which make their home in the water, can exist for one to three years in their immature state, says Kunkel.

Good places to search for stoneflies, says Kunkel, are the White Clay and Red Clay creeks in New Castle County, the Murderkill River in Kent County, and Woodenhawk, a tributary of the Marshyhope Creek, in Sussex County.

Delaware Nature Society has been conducting a Stream Watch program for 20-plus years, says Ginger North, the society’s associate director for natural resources conservation. During that time the Red Clay Creek has shown improvement in its water quality.

“Twenty years ago, the Red Clay was classified as a waterway that was severely impaired,” says North. “It only supported black fly larvae and other macroinvertebrates that can tolerate polluted water. But today, stoneflies can be found in the Red Clay’s tributaries.”

Article by Margo McDonough

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Native Delaware: Seasonal Symphony of Frog Calls Returns

April 19, 2013 under CANR News

On April nights, Holly Niederriter can be found driving slowly down the back roads of New Castle County. Although she appears to be meandering, her excursions are quite purposeful.  A wildlife biologist with the Delaware Department of Natural Resources and Environmental Control, Niederriter is listening for frog calls.

She is one of dozens of Delawareans who drive around after dark searching for frogs as part of the Delaware Amphibian Monitoring Program. The first survey period kicked off in late February, the second starts in a few days, and the final survey occurs in June. Participants are volunteers from the community; most don’t have Niederriter’s wildlife savvy. But they all receive training, and before their debut, take an online quiz to ensure they can distinguish the calls of Delaware’s 16 species of frogs.

American toad by Jim White“Frog calls are an important way to determine where different species occur and how populations are doing over time,” says Niederriter.  “Because most amphibians need both aquatic and upland habitats, they can serve as important indicators of water quality and other aspects of environmental health.”

A colder-than-average early spring made for a slow start to the frog-calling season.  Early April is often the peak of spring peeper season, when the sleigh-bell-like chorus of these tiny frogs reaches maximum volume in vernal pools and marshes. But the beginning of this month was so chilly that the peepers didn’t want to peep.

“Male peepers call to attract a mate but if the weather isn’t warm enough they hunker down and wait it out,” says Jim White, associate director for land and biodiversity management at the Delaware Nature Society and an adjunct herpetology instructor at the University of Delaware. “I didn’t hear a single peeper during the first few days and nights of April.”

Now that temperatures are more seasonal, the spring peepers are out in full force. Recently, they’ve been joined by the pickerel frog, with its snore-like call, and the American toad, which boasts a musical trill. In the Coastal Plain region (Kent and Sussex, plus a sliver of New Castle County), you also can enjoy the throaty croak of the Southern leopard frog.

You need a sharp ear to recognize the call of the American toad, notes Jake Bowman, a UD professor of entomology and wildlife ecology.

“American toads are frequently heard all over our area but rarely do people realize what they are hearing,” he says. “Unlike the commonly recognized sleigh bell call of the spring peeper, the American toad has a high pitched trill. Here on the UD campus, you can find them in most of the wetlands on our farm.”

A father of two sons, Lee, 10 and Ethan, 5, Bowman likes the fact that frogs are “kid-friendly.”

“Probably the nicest thing about toads is that it’s often the only amphibian kids have a chance to handle. My boys love the chance to chase and capture American toads and learn more about them,” he says. “After the boys have checked out the toads, we release them back where we found them.”

Like the Bowman boys, James White, Jr. grew up playing with frogs with his father, Jim White. Now a UD freshman, White is majoring in wildlife conservation and hopes to become a national park ranger.

“For as long as I can remember, I went looking and listening for frogs every rainy, spring night,” says White. “We had a marsh only a few yards from our house so it was never difficult to hear them.”

“I will go herping with my father but because of college it probably won’t be until school is out,” he says. “My favorite frog of spring is the pickerel frog. I always found them pretty frogs and very jumpy, making them a challenge to catch.”

If you want to catch frogs with your kids (or at least see and hear them), Bowman has a few suggestions. Look for terrestrial species on the ground in woodlands and other land habitats. Semi-aquatic species can be seen on the shoreline or surface of freshwater habitats. To find breeding frogs, head to vernal pools and marshes. Warm, rainy nights make for the very best frog-watching. Pack a bright flashlight and plenty of patience.

A spring peeper, for example, is only about an inch long and its brown, gray and green colors don’t stand out, especially at night. “You can practically be on top of them and still not see them,” notes Bowman.

But it’s worth the wait to see a peeper, especially a male one. Males have large vocal sacs under their chins that they pump full of air until they look like balloons about to burst, When they peep, the air is discharged and the shiny sac deflates.

How to Help

To learn more about volunteering with the Delaware Amphibian Monitoring Program, contact Vickie Henderson at 735-8651 or vickie.henderson@state.de.us

Article by Margo McDonough

Photo by Jim White

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Owl breeding season has begun in Delaware

January 29, 2013 under CANR News

Heard any owls lately? Maybe you’ve seen one of these elusive raptors perched on its nest.

If so, please tell Jean Woods.

Woods is the curator of birds for the Delaware Museum of Natural History, one of the organizations supporting the Delaware Breeding Bird Atlas. The atlas is a five-year, state-led project to determine the area bird population and assess any changes since the last atlas, which was held 20-plus years ago.

Data gathering for the atlas was supposed to end in 2012 but there was a bit of a problem, says Woods, who sits on the project’s technical committee. Well, make that a big problem, at least when it comes to owls.

a winter owl in Delaware“We discovered that we didn’t have enough data on the nocturnal birds, especially owls,” she says. “We extended the atlas into 2013 to try to get some additional information.”

Woods is eager to hear from birders or, anyone, frankly, who has heard or seen an owl recently. It can be hard to distinguish the sounds – or sight – of many of the state’s shore and marsh birds. But it’s pretty easy to identify the calls of Delaware’s owls. Their hoots are distinct, and there are only a handful of species in the state.

This is a great time to listen for owls. The end of January marks the start of the breeding season so there’s lots of hooting out there. Owls call for a variety of reasons, including defending territory, communicating with their young, or, as is the case now, to advertise their availability as a mate.

“I can tell that the great horned owls are getting ready to nest,” says Jim White, associate director of land and biodiversity management for the Delaware Nature Society. “I’ve been hearing great horneds when I take the dog out for a walk.”

Delaware has four species of owls that are year-round residents – the great horned, barred, barn and Eastern screech, according to Chris Williams, a University of Delaware associate professor of wildlife ecology in the College of Agriculture and Natural Resources. The great horned owls are the first nesters; they’ll soon be followed by the barred owl and barn, and finally, the Eastern screech owls.

Three more species of owls – short-eared, long-eared and Northern saw-whet – are regular winter migrants to Delaware. A fourth species, the snowy owl, appears sometimes in what is known as an irruption, says Williams.

2013 isn’t shaping up to be an irruption year for snowy owls. But, on the plus side, there are a good number of Northern saw-whets here this winter, says Woods.

Four Delaware owls are considered to be “species of special concern” – the barn, barred, short-eared and long-eared, according to Wayne Lehman, a regional wildlife manager with the Division of Fish and Wildlife. Lehman bands juvenile barn owls every year, from May to July. Banding is easiest then because the fledglings are still on the nest and unable to fly.

The state has been banding barn owls since 1996. It also has established nesting boxes for owls in state wildlife areas.

“Banding provides valuable information on an owl’s life span, home range, nest site fidelity and migratory patterns,” says Lehman.

If you want to go on an owl prowl, set out after dark, especially on windless nights, says White. However, a few species aren’t strictly nocturnal. The Eastern screech – a short, pudgy owl with a large head and almost no neck – often exhibits a burst of activity just before dawn and at dusk.

To increase the chance of success, head to Port Mahon Road in Little Creek Wildlife Area, east of Dover. This is known as the No. 1 spot in the state to see owls — the short-eared owl likes to hang out here. And you won’t need to wait until dark – the short-eared starts hunting in late afternoon, when the sun is setting. This species is a migrant, so get to Port Mahon Road soon. By March, the short-eared will be returning to Newfoundland and other northern locales to begin breeding season.

How to help

If you see or hear an owl in Delaware let Jean Woods know so she can add this data to Delaware’s Breeding Bird Atlas. Contact her at 658-9111, ext. 314 or via email at jwoods@delmnh.org.

Not sure which species you’re hearing? Check out owl calls on All About Birds.

Learn more

On Feb. 10 there will be a program on “Owls and Other Winter Raptors.”

Look for great horned, Eastern screech, barn, barred, short-eared, and other owls on a day-long program with Jim White. The program has a good track record – owls have been spotted every year. To register, call 239-2334.

Article by Margo McDonough

Photo courtesy of Jim White, Delaware Nature Society

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Stewart studies birds to understand trade-offs between reproduction, immunity

November 20, 2012 under CANR News

Does parenting take a toll on the immune system?

If you’ve ever been the parent of a newborn who demanded to be fed every three to four hours, your gut instinct tells you the answer is an absolute, unequivocal yes.

University of Delaware post-doctoral researcher Ian Stewart is conducting research to answer this question a bit more scientifically. His subjects – tree swallows – make human parents look like slouches. Both the mother and father tree swallow feed their hatchlings every five minutes, 12 hours a day.  (It should be noted, though, that their parenting gig is much shorter than ours — after 17 or 18 days the young leave the nest.)

Stewart is studying these small, migratory birds to better understand the trade-offs they make between reproduction and immunity. His research could potentially help scientists who study human biology better understand our own immune system and its stressors.

Stewart is part of a young but growing interdisciplinary field called ecoimmunology, which combines aspects of immunology with ecology, biology, physiology and evolution. He chose to focus his research on tree swallows and bluebirds because both are fairly tolerant of human interaction. “Some birds don’t like being observed but tree swallows and bluebirds don’t get stressed from being watched or handled,” notes Stewart.

There’s another very important benefit to working with these birds — since they nest in boxes, not up in the trees, they’re a heck of lot easier to catch.

Throughout the breeding season, Stewart catches the parent birds, injects them with a harmless antigen and releases them. Then, he re-catches the same birds a few days later to take blood samples and assess each bird’s immune response to the antigens.

“Some of the tree swallows work harder at parenting,” notes Stewart. “It may be because the bird has four hatchlings to feed instead of just three. Other times, the bird is simply more energetic at taking care of its hatchlings, regardless of brood size.”

“We’re monitoring the reproductive effort of the adults – mostly the rate at which they feed their nestlings – so that we can test whether the adults that are working harder produce weaker immune responses,” he says.

Stewart is conducting his research at Coverdale Farm Preserve, a 352-acre tract in Greenville owned by the Delaware Nature Society. The preserve already had 50 bird boxes in place last spring, when Stewart began his field work, and he installed another 50 boxes.

Now that it’s autumn, Stewart spends most of his time in the lab, crunching the data and performing immune assays on the samples he collected.  But earlier this season, he was at the preserve by 7 a.m. every day and after a full day of catching and observing birds, would head to the lab each evening to centrifuge the blood samples for storage.

“Prof. Mike Moore is overseeing my research and I had a grad student, Andrew Hydrusko, assist me, but I worked alone a lot,” he says. “So I enjoyed it when school groups passed by the bird boxes and there was time for them to learn a bit about my bird research. They loved to help catch the birds.”

“Ian’s work is quite interesting,” says Chris Williams, a UD associate professor of wildlife ecology. “One might think that having more offspring would improve your chances of passing off your genes to the next generation. However, if the parent’s health is compromised to make such an effort, natural selection may have something else to say about it. The evolutionary trade-offs between maternal health and maximum number of young ultimately produces optimal clutch sizes.”

So what’s the verdict — do parents shortchange themselves if they devote more resources to their offspring?

Stewart is still analyzing this year’s data and has another year of field research to go. But the preliminary answer, for tree swallows, appears to be yes. As for humans, he will defer to sleep-starved parents of newborns and let them have the final word.

Article by Margo McDonough

Photo by Danielle Quigley

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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

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Butterfly season only average, according to UD entomologist and others

July 17, 2012 under CANR News, Cooperative Extension

Brian Kunkel’s weekend strolls at Middle Run Natural Area make him see red – not because he’s angry but because the red admiral butterfly has been abundant at this 850-acre park east of Newark. A large, red-banded butterfly, the red admiral has been seen in large numbers throughout Delaware this summer.

“The red admiral is experiencing an irruption – a rapid and irregular increase in population numbers,” says Kunkel, an entomologist with UD Cooperative Extension. “It’s not just here in Delaware; this irruption also has been reported in New Jersey, the Poconos, western New York and other Northeastern locales. The last time a red admiral irruption was seen locally was 2001.”

The red admiral is the bright spot for Delaware butterfly watchers this summer. All in all, it’s shaping up to be just a so-so season for butterflies.

“Butterfly numbers were good at the end of May and into June but then things really backed down,” says Sheila Vincent, a group program coordinator for the Delaware Nature Society who maintains Ashland Nature Center’s Butterfly House.

“Mid-July to mid-August is typically the peak of butterfly activity in Delaware but we’ve seen fewer individuals flying,” says Vincent, “Right now, I don’t think we’re going see a repeat of 2011 and 2010, both of which were very good years for butterflies.”

Butterfly populations are influenced by a complex interplay of temperature, moisture and food supply. Different species are impacted by different factors. For example, a species that overwinters in the adult form – such as the mourning cloak — will have better survival rates in milder winters, says Kunkel. If the butterfly’s host plant flourishes during a rainy spring, odds are that butterfly will do well that season, too.

“With so many factors influencing population density, I can’t begin to speculate on why overall butterfly numbers appear lower this year,” says Kunkel.

Delaware has about 120 species of resident breeding butterflies. Considering that most states have about 100 species, Delaware is a pretty good spot for butterfly watching.

“Delaware is home to both the Piedmont Plateau, in the north, and the Coastal Plain, in the middle and southern parts of the state. This makes for a greater diversity of butterflies,” says Vincent. “For example, we don’t get cloudless sulphur butterflies in the Piedmont but on occasion you see a straggler cloudless sulphur fly up from the Coastal Plain.”

If you want to attract butterflies to your yard, Kunkel has two important tips. “First, get lots of plants that caterpillars like,” he says. “Gardeners tend to focus on nectar plants that provide adult butterflies with energy but you also need plenty of food sources for caterpillars – the next generation of butterflies.”

Most caterpillars eat only one specific plant or from one plant family. Do your research. If you love the great spangled fritillary butterfly, plant violets, the food source for this butterfly’s caterpillar. If it’s Eastern tiger swallowtails that you’re trying to attract, plant tulip poplar, sweetbay magnolia and black cherry trees.

If you’ve always prided yourself on a flawless, neat-as-a-pin garden, you may not like Kunkel’s second piece of advice – “tolerate insect feeding.”

Caterpillars eat the leaves and stems of plants, which mean, of course, little holes on the leaves of your plants. “If you want to enjoy the sight of the pipevine swallowtail butterfly, with its brilliant blue wings, you’ll have to accept that your pipevine plants are going to get chewed up a bit by this butterfly’s caterpillars,” says Kunkel.

At the University of Delaware Botanic Gardens, feeding the caterpillars is seen as just as important as feeding the butterflies. The gardens’ Lepidoptera Trail, which opened in 2009, features a wide range of plants to attract caterpillars.

“The trail is not a butterfly garden, which is designed to attract butterflies to feed on nectar,” says garden director John Frett. “It is an ecosystem to attract Lepidoptera throughout their life cycle. It’s a place for them to lay their eggs, which become larvae or caterpillars before entering the inactive pupal stage and then emerging as butterflies, moths or skippers.”

Besides, caterpillars are cool in their own right. “Take the caterpillar of the spicebush swallowtail butterfly. It looks like something out of a cartoon,” marvels Kunkel.

This caterpillar features oversized fake eyes on its thorax and is a garish neon green color at certain stages of development. The fake eyes and bright color is supposed to make the caterpillar look like a snake and thus scare away birds and other predators.

The Lepidoptera Trail, as well as the rest of the UD Botanic Gardens, is open daily from sunrise to sunset for free self-guided trails. For more info, go to http://ag.udel.edu/udbg or call 302-831-0153.

Article by Margo McDonough

Photo by Brian Kunkel

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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

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Delaware Nature Society Names Burr Monroe Downstate Backyard Wildlife Habitat Coordinator

April 12, 2012 under CANR News

The Delaware Nature Society has named Burr Monroe its new backyard wildlife habitat coordinator for Kent and Sussex counties. He will be based at Abbott’s Mill Nature Center in Milford.

Monroe graduated from the University of Delaware in 2005, where he majored in wildlife conservation and received a minor in landscape horticulture.

Monroe has nine years experience managing natural resources for residences, municipalities and non-profits.  He has worked on ecological restoration, environmental assessments, stormwater management projects, landscape design, native plant propagation, educational outreach and more.

In addition to his new position at the Delaware Nature Society, Monroe is a restoration ecologist with Tributaries, an ecological consulting firm in Georgetown.  He also has worked for firms in Harbeson, Rehoboth Beach and Santa Barbara, California.

“I am pleased to strengthen our successful Backyard Wildlife Habitat program in Sussex and Kent counties,” says Brian Winslow, executive director of the Delaware Nature Society. “Habitat stewards previously had to travel from New Castle County to serve the needs of downstate residents who wished to certify their properties as backyard habitats.”

“With Burr’s knowledge of native plants and stormwater issues, we will be able to more effectively work with downstate homeowners, businesses and schools to improve habitat for wildlife on their properties. By creating these wildlife habitats we also are improving water quality in the Delaware and Chesapeake bays and their tributaries,” adds Winslow.

A resident of Georgetown, Monroe is an active community volunteer for Delaware Adopt-A-Wetland. When he is able to find the time, he enjoys surfing at the Delaware beaches.

For more information about the Backyard Wildlife Habitat program, downstate residents should contact Monroe at 422-0847 or burr@delawarenaturesociety.org. New Castle County residents should contact Greg Gagliano, 239-2334, ext. 142 or greg@delawarenaturesociety.org.

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Birds aren’t flocking to backyard feeders this winter

February 13, 2012 under CANR News

What’s in short supply this winter? If you said snow you guessed the first (and obvious) answer. But you may not have noticed what else has been scarce — birds at backyard feeders.

“Our customers are talking about the fact that fewer birds are coming to feeders this winter,” says Charles Shattuck who, with his wife, Kathy, owns Wild Birds Unlimited in Hockessin. “I’ve heard reports of fewer birds at feeders across the East Coast.”

Although no one can say exactly why birds are staying away, Shattuck has a hunch that lack of snow and mild temperatures are at least part of the reason.

When Shattuck takes a walk through his 14-acre property, he sees plenty of birds in bushes and brambles. But not so many at the feeders, seed logs and suet feeders near his deck and kitchen windows. “Think about this past Wednesday, when it was 60 degrees,” says Shattuck. “The birds can still find bugs to eat when it’s that warm. They don’t need to come to my suet feeders.”

“It’s been a very light winter in terms of bird activity at feeders,” concurs Derek Stoner, an avid birder and naturalist at the Delaware Nature Society. “The big flocks of songbirds — sparrows, juncos, cardinals, titmice, chickadees — are around, but they are dispersed widely. Since we’ve not had extended periods of cold or snow cover, the birds have been fine and doing well with what nature provides.”

When northern Delaware did have a light dusting of snow Jan. 21, the birds decided to pay Shattuck a visit. “Even a small amount of snow drastically changed the activity level at my feeders,” he says.

Several northern species, like red-breasted nuthatches and pine siskins, haven’t arrived in Delaware at all – probably because weather conditions and food supply have been adequate in their breeding grounds in the boreal forests, says Chris Williams, a University of Delaware associate professor of wildlife ecology.

“Pine siskins sometimes appear in Delaware in great numbers; this kind of irregular migration is known as an irruption,” says Williams. “We had such an irruption in 2009.”

The fact that some northern species are staying away and resident birds are staying in the woods and fields doesn’t bode well for the Great Backyard Bird Count. A joint project by Cornell Lab of Ornithology and other partners, the count has become one of the largest citizen-scientist efforts in the nation. This year’s count starts Feb. 17 and concludes Feb. 20 and provides a real-time snapshot of where birds are across the U.S. and Canada.

Last February, 11.4 million birds were counted. This year’s numbers could be lower unless more participants venture out of their backyards. Any bird sighting can be reported to the Great Backyard Bird Count, not just those in the backyard.

“Last year, I saw a common merganser in the Red Clay Creek and vultures in the supermarket parking lot and included both on my checklist,” says Shattuck, who has participated in the count for eight years. His store, along with Wild Birds Unlimited’s other franchise stores, co-sponsor the count.“You can count birds at a park, go on a guided hike or simply make note of birds in a parking lot – any bird seen during the four days of the count qualifies,” he says.

Williams says he believes that the count offers useful data for ornithologists.  Bird populations are dynamic and constantly in flux. No researcher or team of researchers working alone could document the distribution and movements of so many species the way the Great Backyard Bird Count does, he says.

Solny Adalsteinsson is a graduate student in Williams’ research group and a self-avowed “bird nerd.” Growing up in Wilmington and later Kennett Square, Pa., she enjoyed the blue jays, northern cardinals and white-breasted nuthatches in her backyard in wintertime. As an undergraduate at Penn State, she liked to hike in the mountains and look for common ravens, which aren’t found in Delaware.

When she worked in Kauai, Hawaii, in 2009 and 2010, the seasonal shift in birds was subtler. “Many seabirds spend their lives out on the ocean and return to land only to breed so the return of the Laysan Albatross is a sign of ‘winter,’” notes Adalsteinsson. “In November, the albatross pairs return to their nest sites on Kauai and begin their courtship dances, sometimes right in residents’ backyards.”

You’re not going to spot albatrosses in Delaware but there are plenty of other interesting birds you might see if you join the Great Backyard Bird Count.

A screech owl, yellow-bellied sap sucker and brown creeper were on Shattuck’s tally sheet last year. Other birds spotted in Delaware during the 2011 count include a peregrine falcon, orange-crowned warbler and Baltimore oriole.  More frequently spotted birds were common grackles, red-winged blackbirds, dark-eyed juncos and white-throated sparrows.

To register for the Great Backyard Bird Count, or for more info, go to this website. While you’re there, print out a regional bird checklist to help identify what you see. There also are many good bird identification apps to figure out what you’re looking at, says Shattuck.

Learn more:

Breakfast and the Great Backyard Bird Count, Feb. 17, 8 a.m.-11 a.m. Help count birds and enjoy breakfast, too, at this program at Ashland Nature Center. To register, call 239-2334.

Article by Margo McDonough

Photo by Derek Stoner

This article can also be viewed on UDaily

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CANR student receives National Garden Clubs Scholarship

June 29, 2011 under CANR News

Matthew Fischel, a senior in the College of Agriculture and Natural Resources, has received a $3,500 scholarship from the National Garden Clubs, Inc., one of the leading volunteer gardening organizations in the world. Fischel, a soil chemistry major, was one of 35 recipients, nationwide, of the National Garden Clubs’ scholarship program.

The program promotes study in the fields of agriculture education, horticulture, botany, biology, forestry, agronomy, wildlife science, land management and related areas.

Photo by Danielle Quigley

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