Trilliums, bloodroot, violets - many wildflowers of spring in eastern North America bloom thanks to ants. The tiny six-legged gardeners have partnered with those plants as well as about 11,000 others to disperse their seeds. The plants, in turn, "pay" for the service by attaching a calorie-laden appendage to each seed, much like fleshy fruits reward birds and mammals that discard seeds or poop them out. But there's more to the ant-seed relationship than that exchange, researchers reported last week at the annual meeting of the Ecological Society of America, which was held online. Read More Here.
By Meagan Cantwell
Jul. 27, 2020 , 9:00 AM
To save energy, many insects swivel their head—instead of their entire body—to scan the world around them. Researchers have now replicated this with a tiny camera with a one-of-a-kind arm they can maneuver from a smartphone. The total system weighs just 248 milligrams—less than a dollar bill.
When strapped onto a beetle’s back, the camera can stream video in close to real time. It can also pivot to provide a panoramic view from the beetle’s perspective (as seen in this video). What’s more, when the camera was mounted onto an insect-size robot, the bot used up to 84 times less energy by moving the arm of the camera instead of its entire body.
The technology is one of the smallest, self-powering vision systems to date, researchers report this month in Science Robotics. In the future, scientists could use these tiny cams to gain insight into the habits of insects outside the lab.
The fascinating features and critical role of these nocturnal pollinators
A freshly emerged cecropia moth dries its wings. A type of silk moth, the cecropia is the largest moth species in North America. (Photo by Mark Beckemeyer/Flickr CC BY-NC 2.0)
by Caitlyn Johnstone
July 21, 2020
Chesapeake Bay Program
submitted by Bonnie Beers
Human focus on nature tends to be what we can see and when we can see it during the day. We rightfully champion the busy worker bees, smell the roses and delight in birdsong, yet nature always has new surprises in store. In recent years we’ve begun to discover what happens sight unseen. Flowers fluoresce in brilliant hues beyond the capability of human eyes. Some plants increase the sugar content of their nectar when they detect the vibration of a bee’s wings. And contrary to our assumption that bees and butterflies are the primary players, a lot of pollination happens while we sleep—thanks to moths.
Moths as powerhouse pollinators
Moths are an evolutionary group that dates back way before the dawn of the bees and butterflies. Because we are more likely to see them during the day, humans are more familiar with butterflies than with moths. However, moths outnumber butterfly species nine to one in discovered Lepidoptera (the insect order that contains moths and butterflies). There are more than 11,000 species of moths in the U.S. alone, and they are a wealth of fascinating facts. In comparison to moths, researcher Jesse Barber of Boise University referred to butterflies as, “an uninteresting diurnal [daytime] group of moths.”
A recent study in England found moths are outshining other pollinators, fertilizing more types of plants and flowers that bees overlook. Many bees and butterflies preferentially target flowers rich in nectar. Moths, on the other hand, are generalists, frequenting a wider range of species and visiting those that bees skip. These night shift moths, it turns out, are crucial to pollination.
A rosy maple moth is seen in Howard County, Md., on June 12, 2020. (Photo by Emilio Concari/iNaturalist CC BY-NC)
Their pollination power is due in part to the tiny scales that give moths their fur-like covering. As the moths visit a diverse array of flowers and enjoy the nectar, their fuzzy bodies collect pollen like a feather duster.
While critical to the moths' role in pollination, their fluff actually evolved to confuse the sonar of night-feeding bats. In fact, the evolutionary arms race with bats has been playing out for a long time. Moths can hear, which researchers used to believe developed to help them escape bats and their sonar technology. However, it may be the other way around. Moths and their ears are older, evolutionarily speaking, so it may be that bats evolved their sonar to better capture moths that already have a leg up on detecting a predator’s approach.
Fascinating moth features: The proboscis (the tongue)
A snowberry clearwing, also known as the hummingbird moth or flying lobster, visits bull thistle growing along the Anacostia River on Kingman Island in Washington, D.C., on Aug. 15, 2019. (Photo by Will Parson/Chesapeake Bay Program)
Moths have an elongated appendage known as a proboscis that can adapt to extract nectar from many types of flowers.
These incredible tongues were even written about by Charles Darwin, who marveled at their design and suggested the moths with these proboscises might be the whole reason certain orchids existed. While he was scoffed at for this theory, researchers recently captured footage of a sphinx moth pollinating the beautiful and ethereal ghost orchid using its 30cm proboscis.
Moths are so adept with these tongues that they can even drink the tears of sleeping birds without waking them.
The antennae of a male luna moth, pictured, are wider than those of a female because it uses them to seek out the pheromones emitted by the female, which remains stationary until after mating. (Photo by Mike Keeling/Flickr CC BY-ND 2.0)
As fabulous as they may appear, the feather-looking antennae of some moths are far from decorative. The detailed structure actually helps the male detect female pheromones from up to several miles away, depending on the species. According to Dr Qike Wang in a recent study, the scales that form the antennae are angled to serve the dual purpose of enhancing female scent and diverting contaminants like dust. The special design creates an area of slow airflow around the antennae, helping the scent to linger and increasing the effectiveness of the pheromones around the sensilla (the sensory receptors).
For the lady moth’s part, she is smelling more than the male’s presence. A female moth has the ability to detect reproductive fitness in the male moth’s pheromones. Believe it or not, humans may also have this ability.
Showy emerald moths are drawn to artificial lights. Green in color as adults, the caterpillar form of this insect resembles a crumpled dead leaf. (Photo by Audrey Hoff/iNaturalist CC BY-NC-ND)
“Like a moth to a flame” may be a common phrase, but moths aren’t actually attracted to light itself. When we put lights on our porches and seem to entice moths to it, we’re interfering with the way they orient their world. Moths navigate by the light of the moon, so they keep it at a certain angle to their body. All of the artificial lights we have now are like millions of road signs sending moths in the wrong direction.
When they emerge from their cocoons, moths still look like pudgy piglets with fluff and tiny wings. A newly emerged moth will pump fluid, called hemolymph, into its wings to unfurl them to their full adult span. Using their antennae to help balance, strong muscles in their thorax then move the wings up and down and propel them off in search of mates and flowers.
Moths of the Chesapeake
From the mountains of West Virginia to the lakes of New York and the hills of southern Virginia, the Chesapeake watershed boasts a number of impressive moth species.
The most captivating of our region’s moths, at least color-wise, may be the rosy maple moth, Dryocampa rubicunda. This moth has large eyes and is delightfully fluffy, sporting a cotton-candy-lemonade coat of bubblegum pink and bright yellow. As the name suggests, rosy maples gravitate to maple trees.
Rosy maple moths are in the silk moth family, Saturniidae, which sports several stunning species that can reach close to the breadth of an adult human’s hand. Silk moths in the Chesapeake are numerous and include such members as the Polyphemus, whose caterpillar eats 86,000 times its body weight, and the woodland-dwelling Prometheus, whose light green caterpillar becomes a black to brown adult moth with a wingspan reaching close to four inches.
The spots giant leopard moth, Hypercompe scribonia, shine iridescent blue. (Photo by Greg Lasley/iNaturalist CC BY-NC)
The largest of the silk moths is the Cecropia, which begins its life as a shockingly adorned and bulbous four-inch caterpillar in shades of black to light green with a bluish hue. Once emerging from its cocoon, the cecropia moth unfurls wings of stunning white, orange and grey that reach almost six inches across. The body is equally beautiful, with a fuzzy red face and feet and body bands of crisp black and white. As the sole purpose of the short-lived adult is to mate and reproduce, cecropia do not have a digestive tract.
Lunas are one of the most recognizable of the silk moths, eliciting admiring sighs from humans lucky enough to spot their fleeting beauty. Lunas do not have a functioning mouth, living only a few days in their adult form. Their pale green, ethereal wings rightfully distract from the body, though this too is strangely beautiful with its creamy coloring and red wine-hued legs. They have long tails on the ends of their wings, which spin as the moth flies. The fluttering of the tails confuses the sonar of bats and affords these night-flying lovelies some additional protection while finding their mates.
Not all moths are nocturnal, and some don’t even look like what we think of as moths. One unusual moth in our watershed is the hummingbird moth, a massive insect many people have seen and mistaken for a bird while watching them visit common garden flowers such as bluebells, bee balm, phlox and verbena. Hummingbird moths like the snowberry clearwing are active during the day, have chunky bodies and even make a humming sound like a hummingbird. If you are interested in seeing these fascinating cross-overs of the animal world, look no further than the leaf piles outside. The loose cocoons of hummingbird moths are often found in leaf litter.
Some moth caterpillars in our region look terrifyingly poisonous but aren’t, like the hickory horned devil. Others look incredibly huggable but should not be touched, like the puss caterpillar. In their turquoise coloring and formidable spurs, the harmless hickory horned devil is one of the few moth caterpillars that does not spin a cocoon. Instead, it burrows into the ground to later emerge as the large and aptly named regal moth. On the opposite end of the spectrum, the fluffy exterior of the adorable puss caterpillar conceals venomous spines that can land a full grown human in the hospital with a single touch. Both cute and innocuous, the adult flannel moth appears to be sporting fluffy boots and is completely harmless. This is a southern moth, so it is found in our watershed only in the far-flung reaches of Virginia. Their cocoons are tough, and abandoned ones serve as ready-made homes for a variety of other insects.
The list of fascinating local moths goes on. Beautiful wood nymphs mimic bird poop, Scarlet Wings live on lichen, Clymenes are also called “goth moths” and vocalize back to bats. The world of moths is diverse and fascinating, and all moths mentioned can be found in our watershed. Stay up late some night and explore what is out there in the world of darkness.
About Caitlyn Johnstone - Caitlyn is the Outreach Coordinator at the Chesapeake Bay Program. She earned her Bachelor's in English and Behavioral Psychology at WVU Eberly Honors College, where she fed her interest in the relationship between human behavior and the natural world. Caitlyn continues that passion on her native Eastern Shore by seeking comprehensive strategies to human and environmental well-being.
Find out by reading this Scientific American article sent in by Bob Powers, Class X
Photo: Radim Schreiber
Night falls in the cove where I’ve set up a camera and tripod, one of those places where the sun sets early thanks to steep terrain and thick tree cover overhead. But the darkness doesn’t last. Not long after twilight, the entire forest is pulsing with hundreds of perfectly-timed, golden pinpoints of light. I reach for my camera and start recording video.
The lights are from Photinus carolinus, the famed synchronous fireflies that display each year in and around the Elkmont section of Great Smoky Mountains National Park. The fireflies are a biological oddity and visual wonder, with males flashing in unison—a behavior that attracts females—for several weeks each summer. While fireflies are a common occurrence here in the East, this particular species is our only true synchronous flashing insect. Its display in Elkmont attracts thousands of people each year.
However, I’m sitting alone in that cove. Elkmont and its crowds are hours away. Instead, I’ve traveled well beyond the national park as a researcher chasing reports of the same species. Synchronous fireflies are known from only a handful of places outside of Elkmont, and if the light show that members of the public have been seeing here is the same one found in the Smokies, we’ll be able to add another population to that list. Counting the insects’ flash pattern carefully, my excitement builds: we’ve located another spot.
Here in the Blue Ridge, though, discovery isn’t always a good thing. In fact, our fireflies have become an emblem of the challenges facing resource managers as public interest in the outdoors grows at an explosive rate. Wildlife is a big part of that draw, and in a world accelerated by social media, natural wonder travels fast. A 2017 video of the Elkmont fireflies shared by the Knoxville News Sentinel racked up nearly 60,000 views on Facebook alone.
That attention can be a double-edged sword. For many, experiencing something as spectacular as a firefly display can ignite a lifetime of learning about the outdoors. But our mountains’ species are often fragile, and too many people striking out to find them can spell bad news. The overwhelming popularity of Elkmont’s display has led to a lottery being used to control the number of visitors hoping to catch the show. In North Carolina’s DuPont State Forest, concern about visitor impacts on another popular firefly species has led to seasonal trail closures.
This conundrum has also touched off a national conversation about the tradeoffs of what we share—and how we share it—related to the outdoors. Some websites are now scrubbing GPS coordinates from wildlife photos out of fear that they might provide a road map for poachers hunting rare species. And a growing group is lobbying for an “eighth principle” related to media and tourism promotion to join the Leave No Trace Center for Outdoor Ethics’ existing guidelines for low-impact outdoor use.
Part of the problem is that buzz about an outdoor activity or destination can spread faster than management plans can keep up. In the West, Instagram posts have transformed little-known alpine lakes into viral outdoor meccas, sending hordes of people flocking to sensitive locations that can be damaged by overcrowding. A video shared by a regional tourism page flashed across my own feed earlier this year, showing folks blasting a caravan of ATVs up the middle of a creek—a practice that can kill aquatic life and pollute water for users downstream.
For the Blue Ridge’s fireflies, the challenges are more subtle. Females need to be able to see the males’ light show to choose a mate, and too many people walking around with flashlights and smartphones can outshine their glow. Even in total darkness, excess foot travel can compact the spongy leaf litter and soil needed for young fireflies to develop. The more people who come looking for the fireflies without knowing how to minimize their impact, the less chance there is that anything will be left for them to see.
So how can we walk that line between sharing outdoor experiences and causing unintended harm? The Leave No Trace Center’s recommendations coalesce around a simple idea: stop and think. “If we can simply encourage people to stop and think about the potential impacts and associated consequences of their actions,” the Center writes in a blog post on the issue, “we can go a long way towards ensuring the protection of our shared recreational resources.”
The Center’s strategy might mean considering what information should accompany a photo or video before posting it, or maybe it could mean waiting to promote a spot that isn’t ready for the spotlight. For tourism officials, a conversation with land managers prior to marketing an asset could help prevent negative outcomes.
Those considerations are on my mind as I watch that newly-discovered population of fireflies. Promoting them could be a release valve of sorts, taking pressure off of crowded firefly-watching spots like Elkmont. But could too much promotion hurt the fireflies before experts can understand how much attention they can handle?
I’m mulling over that question as a car pulls into a nearby parking lot, headlights sweeping across the forest floor. The insects’ light show stops, and a family jumps out. “Where are the fireflies?” they yell. The secret has already gotten out.
Before I have a chance to reply, the group runs off through the night, spotlights in hand, deeper into an emptier woods.
BY WALLY SMITH
Blue Ridge Outdoors
24 JUN 18
By Margaret Renkl
Contributing Opinion Writer, New York Times
May 18, 2020, 5:00 a.m. ET
NASHVILLE — One day last fall, deep in the middle of a devastating drought, I was walking the dog when a van bearing the logo of a mosquito-control company blew past me and parked in front of a neighbor’s house. The whole vehicle stank of chemicals, even going 40 miles an hour.
The man who emerged from the truck donned a massive backpack carrying a tank full of insecticide and proceeded to spray every bush and plant in the yard. Then he got in his truck, drove two doors down, and sprayed that yard, too, before continuing his route all around the block.
Here’s the most heartbreaking thing about the whole episode: He was spraying for mosquitoes that didn’t even exist: Last year’s extreme drought ended mosquito-breeding season long before the first freeze. Nevertheless, the mosquito vans arrived every three weeks, right on schedule, drenching the yards with poison for no reason but the schedule itself. And spraying for mosquitoes isn’t the half of it, as any walk through the lawn-care department of a big-box store will attest. People want the outdoors to work like an extension of their homes — fashionable, tidy, predictable. Above all, comfortable. So weedy yards filled with tiny wildflowers get bulldozed end to end and replaced with sod cared for by homeowners spraying from a bottle marked “backyard bug control” or by lawn services that leave behind tiny signs warning, “Lawn care application; keep off the grass.”
If only songbirds could read. Most people don’t seem to know that in this context “application” and “control” are simply euphemisms for “poison.” A friend once mentioned to me that she’d love to put up a nest box for bluebirds, and I offered to help her choose a good box and a safe spot for it in her yard, explaining that she would also need to tell her yard service to stop spraying. “I had no idea those guys were spraying,” she said.
To enjoy a lush green lawn or to sit on your patio without being eaten alive by mosquitoes doesn’t seem like too much to ask unless you actually know that insecticides designed to kill mosquitoes will also kill every other kind of insect: earthworms and caterpillars, spiders and mites, honeybees and butterflies, native bees and lightning bugs. Unless you actually know that herbicides also kill insects when they ingest the poisoned plants.
The global insect die-off is so precipitous that, if the trend continues, there will be no insects left a hundred years from now. That’s a problem for more than the bugs themselves: Insects are responsible for pollinating roughly 75 percent of all flowering plants, including one-third of the human world’s food supply. They form the basis of much of the animal world’s food supply, as well. When we poison the bugs and the weeds, we are also poisoning the turtles and tree frogs, the bats and screech owls, the songbirds and skinks.
“If insect species losses cannot be halted, this will have catastrophic consequences for both the planet’s ecosystems and for the survival of mankind,” Francisco Sánchez-Bayo of the University of Sydney, Australia, told The Guardian last year. Lawn chemicals are not, by themselves, the cause of the insect apocalypse, of course. Heat waves can render male insects sterile; loss of habitat can cause precipitous population declines; agricultural pesticides kill land insects and, by way of runoff into the nation’s waterways, aquatic insects, as well.
As individuals, we can help to slow such trends, but we don’t have the power to reverse them. Changing the way we think about our own yards is the only thing we have complete control over. And since homeowners use up 10 times more pesticide per acre than farmers do, changing the way we think about our yards can make a huge difference to our fellow creatures. It can make a huge difference to our own health, too: As the Garden Club of America notes in its Great Healthy Yard Project, synthetic pesticides are endocrine disrupters linked to an array of human health problems, including autism, A.D.H.D., diabetes and cancer. So many people have invested so completely in the chemical control of the outdoors that every subdivision in this country might as well be declared a Superfund site.
Changing our relationship to our yards is simple: Just don’t spray. Let the tiny wildflowers take root within the grass. Use an oscillating fan to keep the mosquitoes away. Tug the weeds out of the flower bed with your own hands and feel the benefit of a natural antidepressant at the same time. Trust the natural world to perform its own insect control, and watch the songbirds and the tree frogs and the box turtles and the friendly garter snakes return to their homes among us.
Because butterflies and bluebirds don’t respect property lines, our best hope is to make this simple change a community effort. For 25 years, my husband and I have been trying to create a wildlife sanctuary of this half-acre lot, planting native flowers for the bees and the butterflies, leaving the garden messy as a safe place for overwintering insects.
Despite our best efforts, our yard is being visibly changed anyway. Fewer birds. Fewer insects. Fewer everything. Half an acre, it turns out, is not enough to sustain wildlife unless the other half-acre lots are nature-friendly, too.
It’s spring now, and nearly every day I get a flier in the mail advertising a yard service or a mosquito-control company. I will never poison this yard, but I save the fliers anyway, as a reminder of what we’re up against. I keep them next to an eastern swallowtail butterfly that my 91-year-old father-in-law found dead on the sidewalk. He saved it for me because he knows how many flowers I’ve planted over the years to feed the pollinators.
I keep that poor dead butterfly, even though it breaks my heart, because I know what it cost my father-in-law to bring it to me. How he had to lock the brakes on his walker, hold onto one of the handles and stoop on arthritic knees to get to the ground. How gently he had to pick up the butterfly to keep from crumbling its wings into powder. How carefully he set it in the basket of the walker to protect it.
My father-in-law didn’t know that the time for protection had passed. The butterfly he found is perfect, unbattered by age or struggle. It was healthy and strong until someone sprayed for mosquitoes, or weeds, and killed it, too.
3/26/2020 Entomology Today
If you cleared fallen leaves from your lawn last fall, did you deposit them along the edge of your lawn, where grass meets woods? If you did, you might have unwittingly created an ideal habitat for blacklegged ticks.
In areas of the United States where ticks that carry Lyme disease-causing bacteria are prevalent, residential properties often intermingle with forested areas, and ticks thrive in the “edge habitats” where lawn and woods meet. While many homeowners heed the advice to clear their lawns of fallen leaves in autumn to avoid creating tick-friendly habitat in high-use areas, a new study on tick abundance in leaf litter says raking or blowing leaves just out to the forest edge is not enough.
“Our study showed that the common fall practice of blowing or raking leaves removed from lawns and landscaping to the immediate lawn/woodland edges can result in a three-fold increase in blacklegged tick numbers in these areas the following spring,” says Robert Jordan, Ph.D., research scientist at the Monmouth County (New Jersey) Mosquito Control Division and co-author of the study published today in the Journal of Medical Entomology
Instead, Jordan and co-author Terry Schulze, Ph.D., an independent medical entomologist, suggest homeowners either take advantage of municipal curbside leaf pickup (if available), compost their leaves, or remove leaves to a location further into the woods or further away from high-use areas on their property. “The thing homeowners need to keep in mind is that accumulations of leaves and other plant debris provide ideal host-seeking and survival conditions for immature blacklegged ticks,” says Jordan.
In their new study, Jordan and Schulze set up test plots on three residential properties in Monmouth County, New Jersey, in the fall of 2017 and 2018. Each property had plots at both the forest edge and deeper within the wooded area. Some edge plots were allowed to accumulate leaves naturally, while others received additional leaves via periodic raking or leaf blowing. These “managed” edge plots resulted in leaf-litter depths two to three times that of the natural edge and forest plots.
The researchers then compared the presence of nymphal (juvenile) blacklegged ticks (Ixodes scapularis) and lone star ticks (Amblyomma americanum) in the test plots the following spring. In both years, the results for lone star tick nymphs were inconsistent, but the number of blacklegged tick nymphs in the managed edge plots was approximately three times that of the natural edge and forest plots.
“While we expected to see more ticks along lawn edges with deeper leaf-litter accumulation, we were surprised about the magnitude of the increase in ticks that resulted from leaf blowing or raking,” Jordan says. Fallen leaves provide blacklegged ticks with suitable habitat via higher humidity and lower temperatures within the leaf litter, as well as protection from exposure over winter. Previous research, meanwhile, has shown that people more commonly encounter ticks on their own properties than in parks or natural areas. And that, Jordan says, is a major reason why he and Schulze have been evaluating a variety of residential tick-prevention strategies in recent years. Landscape management is an important—and affordable—strategy to keep ticks at bay, he says. “On properties with considerable leaf fall, the best option would be complete removal of leaves from areas most frequently used–such as lawns, outdoor seating areas, and in and around play sets,” Jordan says. “If this is not possible or practical, leaf piles should be placed in areas least frequently used.
Where neither of these options is possible, or where leaf fall is minimal, mulching in place may be a good option, since this encourages rapid decomposition of leaves, which may reduce habitat suitability for ticks.”
By Jeremy Cox on March 18, 2020, Bay Journal
In Virginia, climate change is about as welcome as ants at a picnic. But across a portion of the state’s southeast, ants are part of the problem.
Since 1960, the annual average temperature in Virginia Beach, the region’s most populated city, has risen about 3 degrees, according to the National Oceanic and Atmospheric Administration. That warming trend has opened the door for fire ants — normally living in more southerly areas — to gain a stubborn foothold in the state, Virginia agricultural officials say.
And it’s growing larger.
“It’s an unfortunate side effect” of climate change, said Eric Day, a Virginia Tech extension entomologist. “We have warmer winters and warmer summers, so it certainly makes for good conditions for fire ants.”
The Virginia Department of Agriculture and Consumer Services announced in December that it was expanding its fire ant quarantine to five new counties and two separate cities. With the addition, the quarantine now spans one or two counties deep along the North Carolina border from just west of Interstate 95 east to the Atlantic Ocean, an area nearly the size of Connecticut.
The quarantine applies to both the black and red fire ant varieties, but the red is more commonly seen in Virginia, officials say. Both damage crops and deliver a nasty sting.
Since their accidental transmittal from South America to the United States in the 1930s, red fire ants have spread across most of the Southeast from the marshy tip of Florida to the windswept plains of Oklahoma.
When the first fire ant infestation was discovered in Virginia in 1989, agricultural officials blamed the interstate trade of plants and sod. They grew so widespread that by 2009 the state announced its first quarantine in the Hampton Roads region.
It has become clear with their continued spread westward along the state’s southern border in recent years that colonies are now marching up from the South on their own, Day said. That shift points for the first time away from humans as a cause for their proliferation in the state and toward a new climate reality, he added.
Fire ants resemble garden-variety ants, making them difficult to spot, experts say. Tell-tale signs of their presence are their mounds, which can reach up to 2 feet high and damage farm equipment. The ants themselves prey on corn, soybeans and other crops, causing further headaches for farmers.
Their sting, though, may be their defining attribute. Anyone who unwittingly wanders into a nest typically emerges with a foot or leg stippled with burning welts that turn into itchy, white pimples that last for days. In extremely rare cases, the victim can suffer deadly anaphylactic shock.
Christopher Brown, who works in purchasing and product development for the Lancaster Farms plant nursery in Suffolk, knows the sensation all too well. “It’s not like getting stung by a bee where it’s one sting and that’s it,” he said. “When you get bitten by a fire ant, you’re going to get bit five to 10 times depending on how long it takes you to realize you stepped on a fire ant mound.”
Suffolk was one of the first areas to be quarantined in 2009. The designation prohibits transporting anything that can carry fire ants out of the area unless it is certified as ant-free. Regulated items include gardening soil, plants, sod, used farm equipment and freshly cut timber.
At Lancaster Farms, workers blend an insecticide called Talstar into their pine bark potting material to kill any ants that may be there, Brown said. It takes a few cents’ worth of the chemical to treat each pot, he estimated; a 15-gallon pot includes about 10-cents’ worth. That expense adds up quickly because the nursery churns out hundreds of thousands of plants each year. “It’s a cost of business,” Brown said.
Fire ants are at the vanguard of an army of pests expected to trudge northward as fossil fuel emissions continue heat up the planet during this century. A U.S. Department of Agriculture-sponsored study in 2005 predicted that warming temperatures will increase the “habitable area” for red fire ants by 21% by the end of this century, pushing their upper boundary about 80 miles northward. By some time between 2080–89, fire ants could occupy a swath of Virginia as far west as Roanoke and stretching along a line bearing northeast toward the District of Columbia, according to the study. Maryland and Delaware can expect to see their first invasions by that time as well, it says.
Fire ants in VA
By Elizabeth Preston © 2020 The New York Times
Are humans the only animals that caucus? As the early 2020 presidential election season suggests, there are probably more natural and efficient ways to make a group choice. But we're certainly not the only animals on Earth that vote. We're not even the only primates that primary.
Any animal living in a group needs to make decisions as a group, too. Even when they don't agree with their companions, animals rely on one another for protection or help finding food. So they have to find ways to reach consensus about what the group should do next, or where it should live. While they may not conduct continent-spanning electoral contests like Super Tuesday, species ranging from primates all the way to insects have methods for finding agreement that are surprisingly democratic.
As meerkats start each day, they emerge from their burrows into the sunlight, then begin searching for food. Each meerkat forages for itself, digging in the dirt for bugs and other morsels, but they travel in loose groups, each animal up to about 30 feet from its neighbors, says Marta Manser, an animal-behavior scientist at the University of Zurich in Switzerland. Nonetheless, the meerkats move as one unit, drifting across the desert while they search and munch.
The meerkats call to one another as they travel. One of their sounds is a gentle mew that researchers refer to as a "move call:' It seems to mean, "I'm about ready to move on from this dirt patch. Who's with me?"
In a 2010 study, Manser and her colleagues studied move calls in a dozen meerkat groups living in the Kalahari Desert in South Africa. Groups ranged from six to 19 individuals. But the scientists found that only about three group members had to mew before the whole party decided to move along. The group didn't change direction, but it would double its speed to reach better foraging grounds.
Biologists call this phenomenon - when animals change their behavior in response to a critical mass of their peers doing something - a quorum response. Manser thinks quorum responses show up in human decision-making, too.
"If you're in a group and somebody says, 'Let's go for a pizza; and nobody joins in, nothing's going to happen;' she said. But if the pizza craver is joined by a couple of friends, their argument becomes much more convincing.
In the spring, you may discover a swarm of bees dangling from a tree branch like a dangerous bunch of grapes. These insects are in the middle of a tough real estate decision. When a honeybee colony splits in two, a queen and several thousand workers fly away from a hive together. The swarm finds someplace to pause for hours or days while a few hundred scouts fan out to search for a new home. When a scout finds a promising hole or hollow, she inspects it thoroughly. Then she flies back to the swarm, still buzzing on its tree branch. Walking on the swarm's surface, she does a waggling, repetitive dance that tells the other bees about the site she found - its quality, direction and how far away it is.
More scouts return to the swarm and do their own dances. Gradually, some of the scouts become persuaded by others, and switch their choreography to match. Once every scout agrees, the swarm flies off to its new home.
In his 2010 book "Honeybee Democracy;' Thomas D. Seeley, a Cornell University biologist, writes that we can learn a lesson from the bees: "Even in a group composed of friendly individuals with common interests, conflict can be a useful element in a decision-making process:'
African wild dog
Like pet dogs, African wild dogs spend some of their time enthusiastically socializing and some of it lazing around. Members of a pack jump up and greet one another in high-energy rituals called rallies. After a rally, the dogs may move off together to start a hunt - or they may go back to resting. In a 2017 study, researchers discovered that the decision to hunt or stay seems to be democratic. To cast a vote for hunting, the dogs sneeze.
The more sneezes there were during a rally, the more likely the dogs were to begin hunting afterward. If a dominant dog had gotten the rally started, the pack was easier to persuade - just three sneezes might do the trick. But if a subordinate dog started the rally, it took a minimum of 10 sneezes to prompt a hunt.
The researchers note that dogs might actually cast their votes via some other hidden signal. The sneezes could help the animals clear out their noses and get ready to sniff for prey. Either way, the wild dogs end their achoo-ing with a decision they all agree on.
Primates, our closest relatives, have provided lots of material for researchers studying how groups make decisions. Scientists have seen gibbons following female leaders, mountain gorillas grunting when they're ready to move and capuchins trilling to one another.
Sometimes the process is more subtle. A group may move across the landscape as a unit without any obvious signals from individuals about where they'd like to go next. To figure out how wild olive baboons manage this, the authors of a 2015 paper put GPS collars on 25 members of one troop in Kenya. They monitored the monkeys' every step for two weeks. Then they studied the movements of each individual baboon in numerous combinations to see who was pulling the group in new directions. The data showed that any baboon might start moving away from the others as if to draw them on a new course - male or female, dominant or subordinate. When multiple baboons moved in the same direction, others were even more likely to come along.
When there was disagreement, with trailblazing baboons moving in totally different directions, others would eventually follow the majority. But if two would-be leaders were tugging in directions less than 90 degrees apart, followers would compromise on a middle path. No matter what, the whole group ended up together.
Ariana Strandburg-Peshkin, an animal-behavior researcher at the University of Konstanz in Germany who led the baboon study, points out that unlike in human groups, among baboons no one authority tallies up votes and announces the result. The outcome emerges naturally. But the same kind of subtle consensus-building can be part of our voting process, too. "For instance, we might influence one another's decisions on who to vote for in the lead-up to an election, before any ballots are cast;' she said.
Below are two articles, one from the Washington Post (submitted by Charlene Uhl) and one from the Audubon Society (submitted by Bonnie Beers) that talk about how we can assist insect populations and feed birds properly. Must reads for backyard naturalists!
Welcome bugs into your yard
When It's Okay (or Not) to Feed Birds
Science Magazine and the Guardian
Climate change could increase bumble bees’ extinction risk as temperatures and precipitation begin to exceed
species’ historically observed tolerances. A new study adds to a growing body of evidence for alarming, widespread losses of biodiversity and for rates of global change that now exceed the critical limits of ecosystem resilience.
Read more about this topic here and here, or read the research study here.
Twenty-Year Study Shows How Climate and Habitat Change Impact One Mantid Species
By Paige Embry, Entomology Today
Ask someone what they know about praying mantids and chances are they’ll bring up the female biting the male’s
head off during mating. It happens, albeit only about 17 percent of the time, but those deaths can be a surprisingly
useful tool when studying mantid population changes over time. It’s one of the pieces of information tracked by
Lawrence Hurd, Ph.D., a professor of biology at Washington and Lee University, during a 20-year study
(1999-2018) of Tenodera aridifolia sinensis, the Chinese praying mantid.
The results were published in January in Annals of the Entomological Society of America.
In the last few years, studies finding widespread declines in insect abundance have made headlines. Hurd’s
long-term study uses one insect in one northern Virginia field to show how such declines can happen. Although the study only followed one species, Hurd and coauthorsnote that the findings should apply to other insects and spiders with a similar life cycle.
For this study, Hurd made good use of his resources. He had an insect of unusual size (7-10 centimeters) that beginners (his college ecology lab students) could easily recognize and catch. He also had a nearby field beginning its natural succession, which functioned as a laboratory because the mantids couldn’t easily escape from it. No other suitable fields were close by, and the mantids aren’t very mobile.
Five times between 1999 and 2018, on approximately the same day in September, Hurd sent his students across the
field in a “skirmish line” to collect, mark, and note every possible T. a. sinensis. Hurd writes in an email, “I always
try to base it [the class] on gathering good, usable data instead of just make-work data collection on a question that
has already been answered.”
To assess the reproductive success of the mantids, they went back after the first frost to collect the oothecae (eggs
laid in a gooey substance that hardens into a protective case). They brought the oothecae back to the lab, weighed them, and then returned them to the field. For the oothecae found on the stems of herbaceous plants, that meant “tying [them] on with sewing thread run through the dried foam surrounding the eggs.” Mantids do well in flowery fields with lots of arthropod prey. When succession trends in an area lead to more trees, the population of mantids should shrink. Over the 20 years of this study, two-thirds of the open field area was replaced by trees, and the number of mantids decreased dramatically.
However, succession was not the only factor impacting the mantids—climate change was as well. When a Chinese praying mantid lays her eggs, the sex ratio is even. By the time the mantids reach adulthood, males outnumber females. Once mating begins, the percentage of males starts to fall, prey to the females as well as any other
predators in the field. Eventually, the females become more common. Even though Hurd and the students sampled on essentially the same calendar day (September 12, 13, or 14) each year, they found that the proportion of males to the total population declined from more than 60 percent in 1999 to about 25 percent in 2018, showing that the mantids were further along in their life cycle.
It’s no surprise. For the last 40 years the growing season in northern Virginia has gotten longer and the summers hotter, so the mantids both hatch and reach maturity earlier. This means that some eggs may hatch before frost can put them into diapause, leading to death of the young nymphs and potentially adding to the population losses caused by the successional change.
In 2018, Hurd and his students found only three oothecae. In the fall of 2019, he saw no mantids, and found no oothecae after the first frost.
This study demonstrates the potential double whammy of habitat loss—even a naturally occurring one—and climate change. Hurd writes, “People are becoming worried about having to include insects in the mass extinction episode that many (including me) feel is already underway.” He says when he talks about this, people often respond with, “‘We gotta worry about bugs, too?'”
Unfortunately, as this study illustrates, the answer to that question is “yes.”
Find this article in Entomology Today here.
Find other articles on declines in insects and biodiversity on the Reading Corner page.
World’s fireflies threatened by habitat loss and light pollution, experts warn
Lightning bugs cannot signal to one another to mate if there’s too much light at night.
By Ben Guarino
Feb. 3, 2020 at 12:22 p.m. EST
(shared by Charlene Uhl, Class X)
Nearly 2,000 species of fireflies flit, crawl and sparkle across the planet. Some of these lightning bugs are doing fine. Others are not.
A survey of 49 of the world’s firefly experts, published Monday in the journal BioScience, has identified the most serious threats to the animals. Habitat loss, in almost all of the regions surveyed, is a problem. Other threats include artificial light, which disturbs their mating rituals; pesticides, which can harm the insects or their invertebrate prey; and water pollution, for species that have an aquatic stage.
The report is not a census of the world’s firefly population. But it is “the very first time that we’ve gathered information — this is based on expert opinion — about what the most prominent threats are to the fireflies in different parts of the world,” said study author Sara M. Lewis, a biologist at Tufts University.
“For the last decade or more, people have been anecdotally reporting that they’re not seeing fireflies where they used to,” Lewis said. “Good census data over the past few decades” exists for some species, such as Malaysia’s synchronous fireflies and the common European glowworm, Lewis said. “We know that those populations are, in fact, declining.”
Elsewhere, however, firefly literature remains “kind of obscure,” she said, and the research community is relatively small.
This poll of firefly experts was the “next best thing” to traveling back in time to count firefly populations, said University of Florida entomologist Marc Branham, who was not a member of the research team. He has been told many anecdotes of missing fireflies. And often, he said, they’re believable. Fields once full of flashing insects “are so obvious, in a sort of a sad sense,” when the light vanishes, he said.
“One of the things we’ve kind of taken for granted is that fireflies will always be here,” said naturalist Ben Pfeiffer, founder of the nonprofit Firefly Conservation & Research organization and one of the firefly experts who was surveyed. “And we’ve been terribly wrong about that.”
In 2018, the International Union for Conservation of Nature created the Firefly Specialist Group, co-chaired by Lewis, to determine whether certain firefly species should be listed as threatened or endangered. “That’s something we’ve never seen happen for a firefly species,” Fitchburg State University biologist Christopher Cratsley said. Cratsley was not a member of the study team.
The survey, Lewis said, represents a first step in that process. She cautioned that “we don’t know what the relative importance of these threats to fireflies are. We only know the ranking of what firefly experts believe.”
A contrast in firefly health is evident in the eastern United States. There, Photinus pyralis -- also known as the big dipper firefly, for the dipping J-shape path the beetle makes as it flies — remains a common sight at dusk. “It’s a very weedy species. It’s a habitat generalist,” Lewis said. These fireflies swoop over rural meadows and the streetside gardens of the District. “We’re lucky that we have some fireflies that are probably going to be just fine.”
Due east of the nation’s capital, however, the situation is dire for the Bethany Beach firefly. That insect, which produces bright green double-flashes, lives only in Delaware’s coastal freshwater wetlands. Residential development has imperiled the species, and in May the Center for Biological Diversity and the Xerces Society for Invertebrate Conservation petitioned the Interior Department to add the firefly to the Endangered Species List.
Artificial light at night can confuse the fireflies and glowworms that use bioluminescence for mating rituals. In the United Kingdom, female glowworms climb up to perch at the tips of vegetation and glow to attract males. “A number of different studies have shown that artificial light in a glowworm habitat actually prevents the males from finding the females,” Lewis said.
Background illumination can also mess up the animals’ sense of timing. “I’ve seen fireflies in New York City that begin courting at like 4 in the afternoon in the summertime, which is not the right time,” Lewis said.
In countries such as Japan, Malaysia and the United States — particularly where there are synchronous firefly displays, like the Smoky Mountains — firefly tourism attracts about 200,000 visitors per year, Lewis estimated. Well-meaning tourists may not realize they are endangering the animals they wish to appreciate. “If you have a lot of people who are tromping through the firefly’s habitat, they’re stepping on larvae” or flightless females, she said.
Some places have taken precautions against trampling feet and have developed firefly sanctuaries with elevated footpaths. A recently enlarged firefly preserve in New Canaan, Conn., is the first of its kind in North America, Cratsley said, at least as far as he was aware.
“The land trust was immediately adjacent to a large mansion — a beautiful home,” he said, of his visit in summer 2019. “But you could go from being surrounded by fireflies to a complete dead zone, of nothing, in that manicured lawn.”
The firefly experts encouraged people to join monitoring groups such as Firefly Watch, a citizen-science project run by Mass Audubon that has partnered with Cratsley, Lewis and other researchers.
“If people are willing to spend five or 10 minutes each week out in their backyard figuring out what kind of fireflies they have and then counting their flashes,” Lewis said, “we think we could begin to gather the kind of long-term data that we need to figure out what species are in trouble.”
Where Light Pollution Is Seeping Into the Rural Night Sky (click here)
Submitted by Barry Buschow
Commercial pumpkin growers routinely rent honey bees so they have enough insects to pollinate their crops, but a new study published in the Journal of Economic Entomology suggests that wild bees can do the job for free. The three-year study found that wild bumble bees and squash bees could easily handle the pollination required to produce a full yield of pumpkins in all of the tested commercial fields, according to Carley McGrady, the lead author of the study.
The pumpkin study was part of a broader initiative, called the Integrated Crop Pollination Project, or Project ICP (http://icpbees.org/), which was headquartered at Michigan State University and funded by the U.S. Department of Agriculture’s Specialty Crop Research Initiative. To read more, click here.
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