​Mosquitoes are an important public health and nuisance pest that require season-long management. Maybe you have seen news reports recently about mosquitoes and West Nile virus and thought, "Is there anything I can do to help?” Today’s blog shares a little information about mosquito biology and what you can do to manage mosquitoes in your own yard and community this summer.

​Mosquito bites are annoying and itchy, but mosquitoes are more than a nuisance—they can transmit microscopic organisms that cause disease, too. In most counties in the United States, there are over 30 types, or species, of mosquitoes present. Importantly, not all types of mosquitoes are capable of spreading disease. In fact, some types of mosquitoes do not feed on humans at all! 

The best way to kill mosquitoes and reduce their numbers uses an integrated approach. Integrated mosquito management collects data to make informed treatment decisions and uses all control tools available and reasonable. These treatment decisions can include a lot of different tactics such as recruiting members from the community (you!) to help! 

​ACTIONS YOU CAN TAKE
 
Because mosquitoes spend a lot of their life swimming, the “tip and toss” method is a great way to reduce mosquito numbers. Once a week, tip and toss the accumulated water out of any items around your home. That is all it takes to get rid of these potential breeding sites! Remember, even a bottle cap full of water is enough to hold mosquito larvae and produce adult mosquitoes. 
 
If you want to go a little farther, consider these water-removing actions as well:

• Clean and maintain roof gutters that can also hold water. 
• For larger containers, drill holes into the bottoms and sides to allow for drainage or turn any unused containers upside down to prevent water accumulation. 
• Depressed areas in the lawn can also create puddles. Folks can solve this problem by top dressing their lawns.

​Insecticide resistance can have troubling costs for insects. What happens when resistant insects start rejecting potential mates? Will the population revert back to susceptibility? Not necessarily. Read on to find out more about a unique, unintended consequence of behavioral insecticide resistance in a common urban pest. 

​Previously, Bug Lessons mentioned how insecticide resistant German cockroaches started to avoid glucose (a type of sugar). Sugary, sweet baits used for managing these insects are also insecticidal. By avoiding sugar, the cockroaches ultimately also avoid the bait. Now, researchers have discovered that female cockroaches that avoid glucose (GA-females) often reject males attempting to mate.
 
WHAT DOES SUGAR HAVE TO DO WITH COCKROACH MATING?
 
Nuptial gifts are small “treats” that animals give to one another to help increase their chance of mating. (Think about that next time your partner gives you a box of chocolates.) This “gift-giving” practice is common in the insect world. For German cockroaches, males present females with a nuptial gift of body secretions that contain sugars and fats. This gift holds the female’s attention long enough for the males to mate.

​However, the nuptial gift that males provide to females contains sugar. Researchers noticed that GA-females turn down the nuptial gift presented to them by most males. As a result, they are rejecting successful mating too. This is counter to what we would expect, since most insects must mate to survive. Why do these females reject the gift, especially since the sugars in the male nuptial gifts are not glucose?
 
SOLVING THE PUZZLE
 
To understand why females were leaving mating events early, researchers started matching up different pairs of cockroaches and observed what happened. Females that avoid glucose most often avoided mating with normal males. (Normal males do not avoid glucose.) However, GA-females feeding on nuptial gifts from males that also avoid glucose (GA-males) did not interrupt mating as quickly. 

​FINAL THOUGHTS
 
The insecticides we use for pest management can affect both the behavior and physiology of insect populations. We need to understand exactly how we are modifying populations with insecticides because unintended consequences that make pest management more difficult can occur. 
 
According to Dr. Coby Schal, an author on the study, “We are constantly in an evolutionary battle with cockroaches. Evolution can be sped up tremendously in the urban, human environment because the selection force imposed on insects, especially inside homes, is so intense.” This study provides yet another timely reminder of the importance of science-based pest management to delay insecticide resistance and other possible unintended consequences.

​Ticks spread a lot of disease in the U.S. If we understand where ticks live, can we stop the spread of tick transmitted disease in its tracks? A new study published by scientists at the CDC claims that maybe we can. Read on to find out exactly how researchers are trying to reduce illness spread by ticks through surveillance and monitoring.

Pathogens transmitted to humans by ticks can cause severe illness, even death. Additionally, allergic responses to tick bites, such as alpha-gal syndrome, can severely impact people’s quality of life. In the U.S., tick transmitted diseases account for over 75% of reported illnesses spread by vectors (animals such as insects and ticks that spread pathogens to other animals). In fact, cases of tick transmitted disease more than doubled from 2004-2016 according to the CDC.
 
Some of the problems created by ticks are new and/or poorly understood by the medical community. Scientists recently found a new, invasive tick that has the potential to spread germs to humans and animals. However, public health professionals still have questions about native ticks as well, such as the blacklegged (deer) tick.

To produce maps visualizing where ticks and pathogens exist, authors compiled tick surveillance data from 2004-2021 by analyzing surveillance records, published research, and archives from public health websites. The results give us the most current idea of where blacklegged ticks reside in the U.S. as well as where exposure risk is highest for some common illnesses. 
 
The CDC data also revealed that Lyme disease (caused by two types of bacteria) is the most widely reported illness- found in 476 counties, 29 states, and the District of Columbia. Authors noted that pathogen distribution is narrower than tick distribution, and disease cases are likely underreported. For instance, many people do not know that they have Lyme disease and are misdiagnosed. 
 
The authors of this paper are filling huge knowledge gaps, especially for areas where ticks are occurring for the first time. However, this study only focused on two species of blacklegged ticks and seven pathogens that cause the following diseases: Lyme disease, hard tick relapsing fever, anaplasmosis, babesiosis, Powassan virus disease, and ehrlichiosis. There are still other species of ticks that can cause other diseases in the U.S. not focused on in this publication.
 
However, not all ticks can transmit pathogens to people. For pathogen transmission to occur, the correct tick species infected with enough pathogen must bite a person. Then, the tick must bite long enough to transmit the pathogen successfully. How long pathogen transmission takes depends on the tick and pathogen in question. Additionally, pathogens and diseases are typically associated with specific ticks. For instance, as of now, scientists have only found Powassan virus in three species of ticks including the blacklegged ticks.
 
FINAL THOUGHTS
 
The authors hope to continue updating the map to keep the public and healthcare providers aware of tick “hot spots.” This is important, because as mentioned above, exposure to ticks could pose a risk to humans. Knowing where ticks exist can help people assess how thoroughly they should check for ticks on their bodies after spending time in habitats likely to harbor ticks (such as woody and excessively grassy areas).
 
Bite prevention is the best way to keep safe. Ideally, you should perform a “tick check” when you have been outdoors for a long period of time even if surveillance data indicates you are probably in the clear. Prevention is the best treatment for disease!

​Scientists in the field of chemical ecology study the chemical interactions among and between living organisms and their environment. For instance, pheromones are important chemicals that animals use to communicate with one another. Popular media often presents pheromones as mysterious chemicals that attract the opposite sex, even though to date, scientists have not identified a single human pheromone. However, pheromones are not just chemicals that lure in a romantic partner. 
 
Technically speaking, pheromones are chemical messages between individuals of the same species that cause a very specific reaction, like a change in behavior. In fact, there are eight types of pheromones used by insects, and experts classify them based on the behavior triggered (e.g., aggregation, alarm, home recognition, and sex pheromones).

​​There has been a lot of media coverage on the Asian giant hornet (Vespa mandarinia) since its invasion into the Pacific northwest in 2019. Popularly called “murder hornets”, the species has caused widespread panic that they are going to hurt people. Fortunately, these hornets pose little direct threat to folks. Unfortunately, there is real concern that the species might establish in the United States. To try to avoid this, there has been a frenzy on the part of researchers to eliminate them from North America.

On that note, people generally use traps to monitor presence and number of pests rather than controlling insect populations. For example, since female Asian giant hornets are responsible for egg-laying and colony production, only capturing males might not reduce the number of hornets if they already mated with a female prior to capture. However, capturing males would help scientists quickly detect overall hornet activity. Thus, pest managers can use pheromone traps in the “identification” and “monitoring” portions of an integrated pest management plan. 
 
FINAL THOUGHTS
 
Chemical ecology can help develop products that protect many different environments from pests. For instance, constantly monitoring for insect activity may stop invasive species from infesting by detecting invaders sooner rather than later. In field crops and forests, pheromone traps have been instrumental in reducing damage to plants. Additionally, these types of products are used in structures to monitor activity of urban and stored product pests. Only by listening and deciphering the secret messages of insects can we use their languages against them.

Insecticide resistance can result in product failures and pest infestations getting out of control. Does that mean all hope is lost? How can people stop insecticide resistance from happening? This week’s blog provides a little knowledge about the traits that allow insects to survive exposure to an insecticide and ways we can prevent this phenomenon from occurring. ​

Scientists group insecticides into classes based on different commonalities they share, such as the way they kill bugs (e.g., their mode of action). For example, the class of insecticides called organophosphates (OPs) all work by interfering with an enzyme involved in nerve function. By interfering with this enzyme, normal nerve signals fail, the insect’s behavior changes, and ultimately, the insect dies. The enzyme affected by the OP is called the target site. The target site is the exact place where the pesticide exerts its killing action.

How is all of this related to insecticide resistance, though? When people repeatedly use products with the same mode of action, resistance can develop. In groups of bugs, a variety of individuals exist with unique physical and behavioral characteristics—and some of them may have genetically based traits that make them less likely to die from pesticide exposure. Using a pesticide kills the majority of individuals in the population. With enough time, the repeated use of the same or similar pesticides kills the susceptible members of the population until only the individuals that can survive exposure remain.

WHAT KIND OF TRAITS ALLOW AN INSECT TO SURVIVE EXPSOURE TO AN INSECTICIDE?

Scientists have identified relatively few ways that insects use to survive exposure to an insecticide.

1. Metabolic resistance. Some insects overproduce or have a more efficient version of an existing enzyme that prevents the insecticide from reaching the target site. Metabolic resistance is the most common mechanism of insecticide resistance.
2. Target-site resistance. Target site resistance occurs when a change at the insect’s target site prevents the insecticide from fully interfering with that process.
3. Penetration resistance. Penetration resistance occurs when the absorption of the insecticide is slowed. A great example of this is the thickening of some bed bugs’ skin, which slows the entry of the insecticide into the body.
4. Behavioral resistance. Insects can avoid an insecticide by changing their normal behaviors. For example, German cockroaches started avoiding sugar baits because the baits often contained an insecticide.

Another strategy uses a product that has two different modes of action (combination product), or a tank-mix. By using multiple modes of action at once, hopefully there will not be individuals in the population with the right mechanism(s) of resistance to overcome simultaneous killing methods. However, over long periods of time, this method may still select for insecticide resistance. For more information on tank mixing, visit the Pesticide Environmental Stewardship website.

Maintaining susceptible individuals with susceptible genes that can interbreed with resistant individuals may also delay resistance. In agriculture, pest managers may do this by not spraying dedicated areas within or near fields to create safe spaces or refuges for susceptible insects. However, in some environments like people’s homes, allowing any insects to persist may not be acceptable.

FINAL THOUGHTS

Evolution is a process that allows animals to survive, even in changing environments. Thus, we should not be surprised that insects can adapt to environments where insecticides are applied. As of now, over 500 species of insects demonstrate some form of insecticide resistance. Once a population has become resistant, professionals have a challenge lessening that resistance.

Reversal of resistance can occur by allowing extensive time between applications of insecticides. However, this is not always reasonable, and no one can know if a resistant population will revert back to the same level of susceptibility. The best way to stop resistance is preventing resistance. With a little bit of knowledge, everyone from consumers to professionals can help delay the selection of resistance.

​Scientists talk about the importance of insecticide resistance often, but what is insecticide resistance? How can insecticide resistance be prevented? This week’s blog discusses some insecticide resistance 101, different ways insects survive insecticide exposure, and why you need to know.

​Bug Lessons regularly advocates for the importance of integrated pest management (IPM) and science-based pest control to effectively manage or eliminate pest problems. Using multiple tools and data-driven treatment decisions to manage pests can reduce chemical insecticide use, which results in fewer environmental contaminates and prolongs the effectiveness of insecticide products. But how? 
 
Sometimes when a person uses the same product or active ingredient repeatedly, insecticide resistance can develop. Insecticide resistance is a change in how sensitive insect populations are to a particular insecticide and may result in failure of the product to control the insects. In other words, the insecticide once killed the bugs, but now they walk right through the spray like a gentle rain in May.
 
HOW DO PESTICIDE APPLICATIONS RESULT IN INSECTICIDE RESISTANCE?
 
Certain environments favor the survival of individuals with certain physical and behavioral traits. When a person uses an insecticide to kill insects, some insects may survive exposure because they are naturally different from the majority of the members in their population. These survivors are the ones who reproduce and, ultimately, spread the genes that made them different to new members of the population. 

WHAT CAN I DO TO HELP?
 
Insecticides are critical for protecting our food supply, reducing disease transmission, and protecting human and animal health. To preserve these useful tools, carefully consider how and how much insecticides you apply. Science-based pest control or IPM is a multi-step process utilizing all tools available and reasonable and uses data to inform treatment decisions.
 
First, try to monitor pest populations and assess the level of damage before deciding whether the application of an insecticide is necessary. The presence of a pest does not always necessitate action or treatment. However, if treatment is necessary, decide whether other control measures can be employed, such as biological controls (predators/parasites), mechanical control, or sanitation. 

When applying insecticides, alternate between different insecticide classes if multiple applications are necessary. When choosing different insecticides to include in your program, consider the following:

• The Insecticide Resistance Action Committee (IRAC) explains the different ways insecticides kill (i.e., mode of action), and the EPA puts the information directly on many product labels. When possible, choose products from different classes.
• Choose an insecticide labeled for, and effective against, the target pest. 
• Follow all label directions for the appropriate application method and rate. 

 
If you think that you might be dealing with a resistant population of insects, report the problem as soon as possible to a local extension specialist at a nearby university. These folks should be able to help assess whether resistance is present, and if so, what type and what to do.
 
Note that in some cases you might be dealing with ‘tolerant’ versus ‘resistant’ pests. Tolerance is not the same as resistance. Tolerance is a natural tendency and is not related to a tangible, genetic change in the population. For instance, you may see a difference in efficacy of a pesticide against different life stages of a pest. Older life stages of an insect may be more tolerant of insecticide application than younger life stages due to morphological characteristics such as cuticle thickness. Again, an extension specialist can help you tease apart any chemical failures you observe and assess the situation for you if you are unsure.
 
FINAL THOUGHTS
 
Insects and other animals can adapt to changing environments—that is why there is so much diversity in the world. However, their ability to rapidly adapt to change also allows insects to survive exposure to insecticides and become resistant, sometimes within a few generations. The best way to stop resistance is to prevent resistance. Using insecticides thoughtfully and sparingly can help prevent resistance by keeping susceptible members in the environment. For more information and resources on using pesticides more effectively, visit the Pesticide Environmental Stewardship website.

Are insects mindless robots? Do they experience more than we give them credit for? New evidence indicates that insects and other arthropods may exhibit a broad range of emotions, feelings, and cognitive abilities that we were previously unaware of.

By Sydney Crawley Ph.D.

Would you think twice about squashing a bug if it was afraid of dying? If it felt pain, would you pause before you applied broad-spectrum insecticides? 
 
A sense of awareness as well as the capacity to have feelings such as, but not limited to, fear or pain is classified as sentience. Sentient animals are typically given more animal welfare protection under the law than animals that are not sentient. In addition, vertebrates (animals with a backbone) are often given more protection than invertebrates (animals that lack a backbone). 
 
Recently, a group of researchers in the United Kingdom (UK) determined that there is enough evidence to classify certain groups of invertebrates as sentient. In their report (linked within this Smithsonian Magazine article), the authors reviewed 300 research studies. Ultimately, they concluded that invertebrates should be protected under animal welfare laws and that slaughter practices like boiling crustaceans alive are inhumane.
 
Crustaceans such as lobsters, crabs, and crayfish are in the same Phylum (one of the ways we group related animals together) as insects and spiders—the Arthropoda. Arthropoda literally means “jointed foot” and contains all animals with jointed limbs, segmented bodies, and skeletons on the outside versus the inside. Although insects were not assessed for sentience in the report, the authors’ conclusions have implications for the way we view animal awareness, especially among closely related taxa. 

​​However, a number of recent studies indicate that some insects are capable of learning, recall, and a host of other behaviors that are indicators of higher-level cognition. ​For example, carpenter ants are capable of decision making and wasps can recognize faces. Impressively, honey bees (Apis mellifera) exhibit multiple behaviors indicative of higher-level cognition. They can count to four, communicate the location of food sources using a waggle dance, and they might even scream/feel fear when they are attacked by predators.
​
FINAL THOUGHTS
 
There is mounting evidence that more consideration should be given to insects when it comes to their ability to feel pain, and we probably cannot dismiss these creatures as simply robotic in nature. Whether or not insects are truly sentient remains to be seen, but based on data, we have to at least acknowledge that insects are capable of learning, decision-making, and other complex behaviors that were previously only associated with vertebrates. 

​Plantlife’s No Mow May™ campaign launched again this year on April 29th, 2022. Advocates of the movement claim that you can do more for pollinators by doing less—just lock up your mower for the entire month. However, does letting your lawn go for one month actually help pollinators? What exactly does the campaign entail, and should you get involved? Read on to hear what all the “buzz” is about. 

Plantlife, a wild plant conservation charity based in the United Kingdom, has asked citizens in the United Kingdom to put away their lawn mowers each May in an effort to increase forage (habitat with food) for pollinators, especially bees. Advocates of the movement encourage members of the community to allow their lawn to grow freely early in the spring (May) so that smaller plants like dandelions and clover can flower. They maintain that this allows pollinators to have a “leg up” on generating their nectar reserves. 
 
At the end of May, when the initiative closes, Plantlife encourages participants to complete the “Every Flower Counts” survey. Survey organizers state that the questionnaire serves as a pollinator “health-check” for the participant by assessing: 

• the types of flowers present in their lawn
• how much nectar their flowers might be producing
• how much nectar their lawn produces throughout the season

As an added participation bonus, each participant receives a unique “Personal Nectar Score”, which is meant to be a reflection of how many pollinators the participant’s lawn can feasibly support. The higher your score, the more pollinator-friendly your lawn is.

Plantife has made multiple claims in their “press pack” that communicate the benefit of the program to pollinator health, including:

1. No Mow May™ resulted in higher flower counts, floral richness, and pollen provision scores versus previous years where the campaign was not employed.
2. Lawns under the right management can be biodiversity hotspots—surveyors recorded almost 100 species of pollinators on their lawns in 2021.
3. A ~1,075 sq. ft. lawn, on average, could produce enough pollen to stock up to six mining bee brood cells and enough nectar to meet the baseline needs of 6 bumblebees a day.
   
4. Dandelion-rich yards are particularly important for wildlife—just 8 dandelion flowers might produce enough nectar sugar to meet an adult bumblebee’s baseline energy needs.

​Pollinators add an estimated $18 billion dollars in crop revenue—their importance in food production should not be understated or underappreciated. The global concern for pollinator health and maintenance is likely one reason why the No Mow May movement has some traction here in the US as well. Outlets like NPR, The Guardian, and The New York Times reported on the phenomenon this year. 
 
Our participation is not entirely new—adoption of the program in the US began in Appleton, Wisconsin in 2020. The result? No Mow May lawns had better bee diversity and abundance versus manicured lawns. In addition, the rusty patched bumble bee, which has been endangered since 2017, was observed in Appleton again for the first time last year. With promising results like these, it is tempting to think that the No Mo May has no downside, right? 
 
Not so fast. Some horticultural educators, such as Pamela Corle-Bennet at The Ohio State University, claim that neglecting mowing for an entire month could kill the grass and encourage weed growth that may increase pesticide use. Additionally, she claims that May might not be the ideal month for nectar-rich plants like clover to bloom in certain geographical areas. For instance she states that in Ohio, clover starts to bloom in June.
 
Griffin Dill, the manager of a laboratory at the University of Maine has concerns about No Mow May, too, but for a different reason—ticks. He worries that the environment that promotes pollinator livelihood would also increase the number of tick encounters they observe in Maine. Bangor Daily News states: “In a perfect world, homeowners could manage yards for tick control and promote pollinator habitat. It’s the unfortunate reality that you can’t do both.” For the record, Bangor is a city in Maine.
 
If you want to protect pollinators this season without encouraging tick presence or risking the health of your grass, the best solution might be to find some middle ground (no pun intended). A nice compromise could be mowing less across the entire flowering season. Research shows that mowing every two weeks could increase the quantity of bees in the landscape. 
 
Mowing less often but not stopping altogether also prevents bees from having issues accessing blooms, which can be a concern if grasses are too long. As an alternative, Plantlife suggests having areas where grass is shorter complimented by areas where the lawn can grow a little taller, if possible. To reduce the presence of ticks, shorter grassy areas should be adjacent/closest to where humans walk around the most. 
 
If the idea of an ‘untidy’ lawn really does not appeal to you or you are restricted by local ordinances, you can still augment pollinator forage by designing a pollinator garden filled with bee- and other insect- friendly plants. The United States Forest Service provides excellent guidance for designing a pollinator garden. You can also reach out to local Master Gardeners and Extension Specialists in your area who may be able to make suggestions tailored to your particular region. Finally, if using herbicides or insecticides in the landscape, always use them according to the label and do not spray on blooms where bees are visiting. This is especially important in the spring and summer when pollinators are exceptionally active. 

Ultimately, there are very few downsides to maintaining a pollinator-friendly yard and trying to improve pollinator diversity and abundance is a worthwhile endeavor. However, the way you decide to support pollinator abundance is a personal choice. Whether you mow less, not at all, or put out a pollinator-friendly garden—minimal or even no effort could help pollinating insects in a major way this season.

​The recent media spotlight on glyphosate has ignited renewed conversation on pesticide safety. Bayer (which acquired Monsanto) continues to address legal action around the claim that the active ingredient (glyphosate) in the popular herbicide Roundup™ causes cancer. The claim and resulting media frenzy has caused discord in both the scientific and political communities. This is understandable, given that evidence for glyphosate’s carcinogenic properties exist, but the Environmental Protection Agency (EPA) has concluded that glyphosate poses “no risks of concern to human health” when used as directed.
 
Media coverage on pesticides can make people anxious, which may be one reason why consumer research shows that people are seeking alternative, “green” solutions. However, terms like “safe”, “organic”, and “all natural” can make a product seem less hazardous to either the user, the environment, or both. That may not always be the case. According to the University of Illinois Extension, “…like synthetic pesticides, organic products have a broad range of toxicity levels.” The article goes on to say that botanical insecticides (pesticides made from plants) can be more dangerous to the environment than synthetic counterparts. 

“Even though these products [Minimum Risk Pesticides] may not require federal registration, most states will require the product to be registered in their state before it can be sold,” said Dr. Janet Kintz-Early, urban entomologist and registration expert with JAK Consulting Services. “States may allow the word ‘safe' as a marketing claim if followed by the phrase ‘when used as directed’.”

Dr. Kintz-Early went on to say that small and start-up businesses may not realize that they are selling a pesticidal product or that their state and/or the federal EPA may require their product be registered. “There are many products for sale on popular e-commerce sites that claim they are ‘safe’ or ‘non-toxic’. These products could literally contain anything,” said Dr. Kintz-Early. “Nothing is safe if you are reckless. All products should be used only as described in the Directions For Use and with an abundance of caution.”
 
Another tricky term is “organic”. Organic pesticides are generally those that come from a natural source. However, nature can produce some very risky substances, such as snake venom, nicotine, and even peppermint. So, while organic active ingredients are naturally derived, they are still pesticides meant to kill pests. Furthermore, the word organic on food is a very specific term defined by the United States Department of Agriculture (USDA). According to the USDA, “Organic is a labeling term that indicates that the food or other agricultural product has been produced according to the USDA organic standards.” Organic, in terms of food production, does NOT mean that no pesticides were used to produce the food.
 
Perhaps the trickiest word of all is “green”. Currently, the term is not defined by any regulatory agency. As a result, different consumers and marketers can interpret the word differently. Additionally, just because a product contains words such as “natural” or “green” does not mean the product contains no risk.

Pesticides allow farmers to grow more food, kill mosquitoes that can spread diseases to people and animals, disinfect surfaces of harmful pathogens in hospitals, and help us conserve food by eliminating pests that eat stored products such as grain (to name just a few). However, whether the pesticide is “green” or synthetic, the best control programs use them as one component of an integrated plan that makes data-driven decisions and utilizes all tools available and reasonable. Undoubtedly, ways to reduce reliance on pesticides as well as the negative environmental impacts they can sometimes have should be explored. However, a “green” pesticide is not always likely to reduce environmental impact simply because the label contains words such as “safe” or “organic”. 
 
For more information on what different words mean or help identifying a “lower-risk” pesticide, please visit the National Pesticide Information Center’s Common Pesticide Questions section.

​For many of us across the U.S., spring has arrived with some much needed sunshine and warm weather. Unfortunately, rising temperatures have also triggered the emergence of some undesirable 6 and 8 legged creatures. Along the east coast, this includes the presence of a new, menacing looking spider. But do not be afraid, looks can be deceiving.
 
Coined the ‘joro spider’ (Trichonephila clavata), this palm-sized arachnid (another term scientists use for spider) invaded from Japan and took up residence in Georgia back in 2014. Recently, a scientific publication claimed that this species had the potential to invade the entire east coast due to its cold hardiness versus other related, native species. The popular press really ran with the finding, crafting sensationalized headlines to warn the public that large spiders would soon be literally “falling from the sky”—pushing the joro spider into the limelight, most likely, undeservedly.
​
​Joro spiders are native to Japan and eastern Asia, and experts think they entered the U.S. in shipping containers. Using websites such as https://www.inaturalist.org/, which allows citizens to report sightings of joro spiders, scientists estimate the current range of this invasive species to be somewhere around 15,500 square miles. 

In spite of a striking appearance (in Japanese folklore, the joro spider turns into a striking woman to prey on unsuspecting men), they do not harm humans or animals and are considered a very passive spider. Although you probably should not handle one, bites are unlikely. Additionally, experts have found that this species has little to no effect on regional agricultural practices or ecosystem functions. They might even be beneficial, as they feed on some pest insects, and might serve as an additional food source for birds and other predators. Thus, unlike other more destructive invasive insects, spiders, and ticks you may have heard of (e.g., spotted lanternflies, fire ants, brown marmorated stink bugs, and Asian longhorned ticks) researchers think the best thing to do with this spider is simply leave it alone. 
 
Right now, there have been joro spider sightings in Georgia, Tennessee, South Carolina, North Carolina, and Oklahoma. They can easily move due to human activity and travel. Time will tell how far they will establish, but over the next decade or so, researchers estimate that the spider’s range will increase in all directions due to their ability to withstand milder climates. 
 
There is no reason to kill these spiders when you see them. Although if you see one outside reported ranges, you could report it to help scientists map their spread throughout the U.S. Additionally if you need assistance with identification, you can work with an extension specialist at a major academic university in your state.
 
You may be tempted to kill spiders when you see them, especially non-native, giant ones that look threatening. However, try not to judge a book by its cover here. This may be a lucky situation where an invasive species actually benefits the area it inhabits. Let’s hope so because, like it or not, it looks like joro spiders are here to stay. For more information on joro spiders, check out this nice article by The Washington Post.​