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.”
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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
03.02.20 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. Meerkats 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. Honeybees 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. Baboons 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. By Erin Blakemore
Washington Post March 14, 2020 at 8:00 a.m. EDT Bee hotels — boxes promoted as good nesting places. “Bee-friendly” farming techniques behind favorite foods. Are the claims true — or just honey-drenched hype? Lila Westreich, a bee researcher at the University of Washington, says companies take advantage of well-intentioned consumers by “bee-washing.” The term, first coined by researchers in 2015, refers to greenwashing, in this case a marketing strategy that makes a product or practice seem beneficial to threatened bees. (Greenwashing evolved from the term whitewashing and means an environmental spin.) In The Conversation, Westreich writes that the practice can actually hurt bees. Bee hotels are advertised as safe nests for bees, for example, but some may be dangerous. The welfare of honeybees may be overemphasized, misleading the public about environmental priorities. Wild native bees are at particular risk. Of the 20,000 or so bee species in the world, only about 4,000 are native to North America — the bumblebee among them. These bees don’t produce honey, and they’re less sociable and well-known than their so-sweet counterparts. The majority of American bees don’t produce honey. Honey bees came to the United States from Europe. Kelsey K. Graham, another bee researcher, calls them the “chickens of the bee world” because they are so domesticated. Unlike hive-dwelling honeybees, which are carefully bred, imported to the country for use in crop pollination and managed, the majority of native bees are solitary and nest underground. They reportedly pollinate up to 80 percent of plants, including many crops. They’re also at risk: In a 2017 study, the Center for Biological Diversity found that more than 50 percent of North American native bee species are declining; 24 percent are threatened with extinction. Native bees are threatened by climate change, habitat depletion and pesticide use — but honey bees get most of the publicity. “While many people are worried about honey bees, it’s also important to understand the jeopardy that native bees face,” Westreich writes. “Companies and organizations use bee-washing to boost their image, taking advantage of the public’s lack of knowledge of native bees.” By bragging about how they help honey bees, notes Westreich, they play down the importance of native species that, unlike honey bees, are actually endangered. They also play up their solutions, such as bee hotels, that can hurt bees by spreading disease. Ready to inoculate yourself against misleading claims about bees? Read Westreich’s article at bit.ly/beewashing By Berni Olson March 3, 2020 About a month ago I saw the movie Beaver Believers. Great movie if you have the opportunity to see it. As I was leaving the thought occurred to me that so much of our environment is now managed. The movie showed how beavers had to be relocated if they were in the “wrong” area or creating dams in the wrong places or damming up areas that would interfere with us humans. There was one woman who rescued beavers and it was amazing how she would take those beavers in her arms and love on them. Last week at our county park, we installed five Bluebird boxes. Again I thought about how we now manage Bluebirds- we build them boxes, make sure snakes, raccoons and house sparrow don’t mess with them, check in with them once a week and provide cleaning services after the babes have fledged. The Bluebirds are counted and watched and well managed. We’ve managed them so well they are now thriving which leads me to another point that I will make just briefly- I think it’s time to move onto another species that needs to be managed and helped to thrive. I believe the Loggerhead Shrike could use our help. Also at our lovely county park, two pollinator gardens have been installed. Again, the word manage comes to mind as we park volunteers discuss when and if we should “clean-up” last year’s dead materials or if we should leave the gardens alone. The discussion continues on as to if we should maybe even leave it half and half to see what would happen. A large plan of the entire park has been created- of how we want it to look. Overall it’s a good thing these pollinator gardens- they are great ambassadors to the general public and those who don’t know about native plants or bees, wasps, ants, and birds and everything else that keeps the gardens humming. I work for a Land Trust and all easements are encouraged to have a forest “management” plan. We had one couple who wanted nothing done with their forest. They only wanted invasives removed if that were to help the forest. The couple had to insist on not having a plan and did not want it managed. They won. On many of the easements when a plan is in place anything that may be done to that forest has to go through the plan. Understandable and a good idea and at the same time there’s that word- manage. About a month ago I also saw the movie, “Jeremiah Johnson”. I walked out of the movie wanting to go and get on my mule and make my way in the wilderness. Fat chance- there’s no place to do that anymore. I pretend when I go out into the woods and surrounding farmland. I pretend I’m exploring for the first time. Sometimes I run into bears- now they are wild- and my mule thinks they are wild. He becomes a bit wild when he sees them. They, the bears get managed if they get to close to humans and invade our space. My friend whom I viewed the movie with said you can still go out to the Bob Marshall Wilderness Area- why yes you can for a visit- not to live- it is a managed area. I’m happy to report that around 1 million acres is home to the largest population of grizzly bears outside of Alaska. I could put my mule in a trailer and head to the “Bob” as it is called and I wouldn’t have to pretend until I had to come home again. Today, I was giving grief to the various invasive species, I have all of them, on the property. Top on my list was Bittersweet. I think there is a cosmic joke here- we can hardly manage the invasives that have invaded our countryside -think about Kudzu- it is wild! And guess what the best manager of Kudzu is- goats- they can consume an acre a day. Ironically invasives seem to be wild- we have a tough time managing some of them and some are downright dangerous, enough to make you have nightmares. So what’s my point today? I’m grieving a bit that there is no more “wild” left-- everything is managed. I seek out places – this year I am climbing to all the peaks in Rappahannock County—to fulfill this need to be in the wild, to see the wild and to be with the wild-- at least temporarily. I feel peaceful there in the wild, I relax a little more, my mind rests and I’m detached from world that’s managed – at least temporarily. Will there be any wild left in 100 years? |
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