By Akito Y Kawahara
Editor's note: According to recent press reports, two Asian giant hornets – a species not known to occur in North America – were found in northwest Washington state in late 2019, and a hornet colony was found and eliminated in British Columbia. Now scientists are trying to determine whether more of these large predatory insects are present in the region. Entomologist Akito Kawahara explains why headlines referring to "murder hornets" are misleading.
1. How Common Are These hornets in Asia, and How Much Alarm Do They Cause?<p>The Asian giant hornet (<em>Vespa mandarinia</em>) is fairly common in many parts of Asia, where it is called the "Giant hornet." Growing up in Japan, I saw them relatively frequently in the mountains outside of Tokyo.</p><p>These insects are large and distinctive, with a characteristic orange head and black-banded orange body. Like any other social wasp, they will defend their nest if the colony is disrupted. But in most cases they will not do anything if people aren't aggressive toward them.</p><p>Giant hornets have longer stingers than a honeybee's, and hornets do not break off their stingers when they sting. Because hornet stingers can puncture thick clothing, people should avoid hornets and their nests whenever possible.</p>
2. Are You Surprised That the Hornets Have Appeared in North America?<p>To some degree, yes. Most likely, a single, fertile queen hornet entered Canada via shipping packaging and created the colony that was discovered in 2019.</p><p>It's easy for invasive species to travel this way. More than 19,000 cargo containers <a href="https://www.smithsonianmag.com/history/policing-americas-ports-108008881/" target="_blank">arrive daily at U.S. ports</a>, and inspectors can only do random searches of shipping containers. One estimate suggests that just <a href="https://www.ncrs.fs.fed.us/pubs/jrnl/2001/nc_2001_haack_004.pdf" target="_blank">2% of shipments</a> are searched for evidence of harmful organisms such as plant pests. Many invasive species are intercepted, but some do get through.</p><p>It's very unlikely that an entire colony of hornets was transferred to North America. Colonies of this hornet are often large, and the hornets would be visible and potentially aggressive if their nest were disturbed.</p><p>A genetic test indicated that one of the hornets found in Washington was <a href="https://news.ucr.edu/articles/2020/05/06/murder-hornets-invade-headlines-not-us" target="_blank">not related to the Canadian colony</a>, but those results have not been published or peer reviewed. The Giant hornet has not been found in 2020 in either the U.S. or Canada.</p>
Four wasp and hornet species often confused with the Giant hornet. Upper left: European hornet (Vespa crabro). Upper right: Common aerial yellowjacket (Dolichovespula arenaria). Lower left: European paper wasp (Polistes dominula). Lower right: Baldfaced hornet (Dolichovespula maculata). gailhampshire (upper left), Gilles Gonthier (upper right), Judy Gallagher (bottom images), all via Flickr, CC BY
3. What Kind of Conditions Do These Insects Need to Live?<p>Giant hornets are fairly common in mountainous regions of Asia, but they're not often seen in large cities or highly urbanized areas. They usually nest at the base of large trees and inside dead logs. The fact that they can't tolerate extremely hot or <a href="https://www.jstor.org/stable/25008806" target="_blank">cold temperatures</a> makes it unlikely that they would spread to very hot or cold areas of North America.</p><p>If active colonies are discovered in 2020 in the Pacific Northwest, which has a more temperate climate, it's possible that they could spread there. However, it is unlikely that this would happen quickly, as foraging ranges of <em>Vespa</em> are only <a href="https://doi.org/10.1371/journal.pone.0185172" target="_blank">about 2,300 feet (700 meters) from their nest</a>.</p><p>The key to prevent spread is surveillance. Anyone in the Pacific Northwest should be alert for Giant hornets while they are outdoors this summer and fall.</p>
4. If More Hornets Are Found, Could They Threaten Honeybees and Other Pollinators?<p>Possibly. Some media posts have described destruction of honeybee nests by what could have been Giant hornets, but honeybees are not these insects' only prey. The hornets feed on different kinds of insects, and bring captured dead prey back to their hive to feed to their young.</p><p>In Japan, beekeepers surround their hives with <a href="https://shop.r10s.jp/diokasei/cabinet/suzume/imgrc0068904247.jpg" target="_blank">wire screen nets</a> to protect them from hornets. North American beekeepers can replicate these with wire netting from local hardware stores.</p><p>Many honeybees in Asia have the ability to protect their hive from intruding Giant hornets by <a href="https://doi.org/10.1016/j.cub.2007.07.033" target="_blank">scorching them</a>. They wait for a hornet to enter their nest, then mob it by surrounding it completely with their bodies. Each honeybee vibrates its wings, and the combined warming of honey bee bodies raises the temperature in the center of the cluster to 122 degrees F (50 degrees C), killing the hornet. Carbon dioxide levels in the nest also increase during this process, which contributes to the hornet's death.</p>
5. Are News Stories About “Murder Hornets” Overreacting?<p>Yes, very much so. In parts of Japan, people consider these hornets beneficial because they remove pests, such as harmful caterpillars, from crops. They are also thought to contain nutrients, and have been used as ingredients in <a href="https://www.splendidtable.org/story/the-japanese-tradition-of-raising-and-eating-wasps" target="_blank">Japanese food and some strong liquors</a>. Some people believe the hornets' essence has medicinal benefits.</p><p>People who live in Vancouver, Seattle or nearby should certainly take note of what these insects look like. They are 2 inches long or more, with a <a href="https://extension.psu.edu/asian-giant-hornets" target="_blank">3-inch wingspan</a>, and have distinctly orange heads and broad striped orange and black-banded abdomens. That's different from typical North American hornets, which have yellow or white bodies with black marks.</p><p>In the unlikely case that you see a Giant hornet in Washington state, do not try to remove nests yourself or spray hornets with pesticides. Cutting down trees to prevent nesting sites is also unnecessary, and can affect many other kinds of native wildlife, including beneficial insects that are needed for pollination and decomposition. Many native insects are <a href="https://doi.org/10.1146/annurev-ento-011019-025151" target="_blank">declining globally</a>, and it's important to make sure these insects are not affected.</p><p>Instead, take a photo from a distance and report it to the <a href="https://agr.wa.gov/departments/insects-pests-and-weeds/insects/hornets" target="_blank">Washington State Department of Agriculture</a>. Photos are essential to verify that identifications are accurate.</p><p>Consider also uploading your images to <a href="https://www.inaturalist.org/" target="_blank">iNaturalist</a>, which is one of the primary sources for information on tracking wildlife. The images are archived and carry data, such as location, time of observance and the insect's morphological features, that scientists can use for research. </p>
Washington State has seen a slowdown in the infection rate of the novel coronavirus, for now, suggesting that early containment strategies have been effective, according to the Seattle NBC News affiliate.
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Removing one gigantic dam can have a massive effect on restoring a river ecosystem.
A Group Effort<p>Large dam removals, like those on the <a href="https://therevelator.org/klamath-dam-science/" target="_blank">Klamath River</a> in California and Oregon, or the <a href="https://therevelator.org/save-southern-resident-killer-whales-extinction/" target="_blank">hotly debated Snake River dams</a> in Washington, get lots of media attention. But smaller dam removals are quietly happening all across the country.</p><p>In the past 20 years around 1,100 dams have been removed in the United States — many of them aging, unsafe structures that had outlived their usefulness.</p><p>That's the story in the Cleveland National Forest, too.</p><p>Not a lot is known about the early history of the dams there, but most were likely built in the 1930s by the Civilian Conservation Corps, a public work program started to help Americans rebound from the Great Depression, says Kirsten Winter, a biologist in the Cleveland National Forest who has spearheaded the dam-removal project. It's not unusual for dams to be built in national forests, but this high a concentration of small dams may be a regional phenomenon in Southern California forests.</p>
Before and after dam removal on San Juan Creek in the Cleveland National Forest. Julie Donnell / USFS<p>The project has generated a lot of interest and a diverse array of partners, including California Department of Transportation, Federal Highways Administration, Orange County Parks, Orange County Transportation Authority, the U.S. Fish and Wildlife Service, California Department of Fish and Wildlife, and the U.S. Marine Corps. The coalition has brought funds, organizational support, technical knowledge and a lot of energy to the process.</p><p>"People are really pretty enthused about removing dams," says Winter.</p><p>Despite all the partners, it's still been a learning experience, she adds, because the dams vary so much in size and accessibility. Some are just a few feet high and 10 feet wide. Others reach 14 feet in height and stretch up to 100 feet across.</p><p>To breach the dams and break apart the mortar, crews employed a wide range of techniques. For sites near roads, they bought in conventional excavators. Steeper canyons required the use of a nimble "spider" excavator. Explosives took down a few dams where appropriate, while other places required sledgehammers and jackhammers. An extra bit of muscle (organizational and otherwise) came from a partnership with Marines from nearby Camp Pendleton. Corps members have helped remove 31 dams since 2018.</p>
Ecological Benefits<p>The biggest benefactors of the dam removals in the Cleveland National Forest will be steelhead — a type of salmonid. Like salmon, steelhead are anadromous, spending their time in both freshwater streams and the ocean. But unlike salmon that return to their natal headwater streams to spawn and die, steelhead will often spawn more than once.</p><p>They're also a key indicator species, says Jacobson. "When they disappear, that means there are probably multiple issues within a watershed."</p><p>In the San Juan, dams are one of them.</p>
Endangered Southern California steelhead spawning in Maria Ygnacio Creek in Santa Barbara County, Calif. Mark H. Capelli / WCR / CC BY-NC-ND 2.0<p>"Dams create a very artificial situation," says Winter. "It's not just that they hold water, but they retain sediment and then they create these weird splash pools below."</p><p>Without the dams, the streams are able to create a more natural gradient and pool structure. That's good for other native wildlife like the arroyo toad and the arroyo chub, both federally listed as endangered, as well as the California newt, a California Species of Special Concern.</p><p>While the process of removing the dams can be a bit messy, "we've seen no negative effects to the habitat or to species due to the dam removal," says Donnell.</p><p>One of the biggest concerns with any dam removal is ensuring that any trapped sediment released from behind the structures doesn't cause ecological problems as it moves downstream. But Donnell says they've timed the removals to account for that and the streams naturally carry large sediment loads during storm events.</p><p>"We're actually doing some of dams in phases rather than all at one time because of the sediment load that's being held behind them," she says.</p><p>In areas where dams have been removed, Donnell has already noticed an improvement. "The bedload and sediment transport have been able to naturally flow once again," she says. "And the channel is starting to adjust back to a natural state."</p>
A Connected Watershed<p>As groundbreaking as the Cleveland National Forest's efforts are, the benefits for steelhead hinge on the downstream initiative.</p><p>Just five miles inland from Doheny State Beach, around the town of San Juan Capistrano, two barriers on Trabuco Creek block steelhead from 15 miles of upstream spawning habitat in the San Juan Creek watershed.</p><p>A quarter-mile-long concrete flood-control channel runs underneath five bridges, including the north- and southbound lanes of Interstate 5. The drop and the speed of water flowing through the hardened channel inhibits steelhead from making it through the gauntlet.</p>
Ripple Effect<p>With the dam removals in the Cleveland National Forest nearing completion, Donnell says she's hoping to soon begin presenting her data and methodologies so others can learn from the project.</p><p>"We've definitely heard from other forests and other districts wanting to know how we went about it, because this is new," she says.</p><p>McClain says American Rivers has been sharing the project's success story because it's a good example of how to think holistically about managing water and restoration opportunities for aquatic ecosystems.</p>
San Juan Creek in the Cleveland National Forest shortly after a dam was removed. Julie Donnell / USFS<p>But it also makes sense fiscally. Why spend money maintaining dams we don't need?</p><p>"Even from a federal budget management perspective, we should be looking at where there may be projects on the federal books that are no longer serving a purpose," she says.</p><p>Thanks to the coordinated efforts in the San Juan watershed, southern steelhead will have a better chance of survival. But efforts to try and aid their recovery also have a larger benefit.</p><p>"We're not only restoring their environment, but also ours," Jacobson says. "We're actually improving the rivers overall."</p><p>And in the process, they may have established a model for mass dam removal across the country.</p>
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Bottled water manufacturers looking to capture cool, mountain water from Washington's Cascade Mountains may have to look elsewhere after the state senate passed a bill banning new water permits, as The Guardian reported.
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The Washington Department of Ecology responded to an oil spill that took place Friday night when a Crowley Maritime Barge was transferring five million gallons of oil to the Shell Puget Sound Refinery, CNN reported.
A massive winter storm dumped snow on the midwest Friday, killing at least nine, before moving east to bring snow and freezing rain to the Mid-Atlantic and the Carolinas Saturday and Sunday, AccuWeather reported.
"We have a strong snowstorm that's stretching 1,400 miles from Kansas to the East Coast," CNN meteorologist Haley Brink said. "St. Louis is seeing its worst snowstorm in five years. We're going to see a significant snow event for the mid-Atlantic to start the year for 2019."
Washington, DC made history Tuesday when its council voted unanimously to transition to 100 percent renewable energy by 2032, the Huffington Post reported. The commitment is part of the Clean Energy DC Omnibus Act of 2018, which also includes measures to reduce emissions from buildings and transportation and gives the nation's capital the most comprehensive climate policy of any city in the country.
With only 74 left in the wild, the Southern Resident orca population in Puget Sound needs help now more than ever. That's why on Thursday, Washington Gov. Jay Inslee's office announced "an unprecedented investment" to help boost the population as well as the Chinook salmon they eat.
"We are undertaking a herculean effort to save these iconic creatures. It will take action at every level of the environment across our entire state," Inslee said in a news release. "We need to restore the ecosystem to one that sustains orcas, salmon and the quality of life for all Washingtonians."
By Shawn Olson-Hazboun and Hilary Boudet
A year after Washington state denied key permits for a coal-export terminal in the port city of Longview, the Army Corps of Engineers announced it would proceed with its review—essentially ignoring the state's decision.
This dispute pits federal authorities against local and state governments. It's also part of a larger and long-running battle over fossil fuel shipments to foreign countries that stretches up the entire American West Coast.
Tuesday, a report written by the company proposing the world's largest fracked-gas-to-methanol refinery was released by the Port of Kalama and Cowlitz County, Washington. The proposed fossil fuel refinery is controversial because of the impacts on both local residents' health and our climate. Despite the company's claim that the refinery could result in a climate benefit, the refinery would consume a stunning amount of fracked natural gas—one-third as much gas as the entire state of Washington.
Results from the U.S. midterm election are mostly in, and, when it comes to what they mean for the environment, they're a real mixed bag.