# What Are Locusts and Why Do They Swarm? ## Highlights ### q1 locusts are a unique pest because they swarm and fly > "Unlike other pests, which are localized, desert locusts can swarm and fly, and an entire region can be wiped out of crops," as the locusts come through and chow down, said Esther Ngumbi, an entomologist at the University of Illinois at Urbana-Champaign who studies agricultural pests and food insecurity. The enormous swarms of desert locusts can be utterly devastating for famers whose livelihoods depend solely on those crops, she said. This would be a good reason NOT to do monocrop agriculture, right? How did people cope with locust swarms before their eggs were in one basket, metaphorically? #nonfic/article - [View Highlight](https://read.readwise.io/read/01fn7b9t9kkkst06cs92ts2xrb) ### q2 serotonin production is triggered by touch > The specific signal that instigates the phase shift varies from species to species, Song said. For example, although both species react to the sight and smell of other locusts in a laboratory setting, the desert locust can shift into the gregarious phase with a touch on the hind legs, whereas the sensitive area on the Australian plague locust (*Chortoicetes terminifera*) is its antennae, he explained. These triggers seem to boost levels of serotonin, the same chemical associated with mood in humans. - [View Highlight](https://read.readwise.io/read/01fn7bbx00k1ynxr5ag53cvmy4) ### q3 locusts display phenotypic plasticity > The two "Jekyll and Hyde" versions of the locust are an example of a phenomenon called "phenotypic plasticity." This happens when the [genes](https://www.livescience.com/27332-genetics.html) of the animal go unchanged, but the behavior and physiology changes in response to external factors. "Certain traits are fixed, and certain traits change in response to the environment," Song said. "This is common across all life forms, including us." - [View Highlight](https://read.readwise.io/read/01fn7bc9pfym5et28sq85rj7md) ### q4 locust phasing is adaptive > One theory to explain why locusts adapted to have such phase changes, according to Song, is that the switch is a response to a changing environment. About 8 million years ago, as Northern Africa shifted from tropical forests to desert, migratory swarming locusts could hop from one oasis of vegetation to the next, or shift back to a solitary phase if there was plenty of food and space in one place. - [View Highlight](https://read.readwise.io/read/01fn7bd3vfekfyt8c2tk0s4t2w) ### q5 huge locust plagues can last years > Locusts are [herbivores](https://www.livescience.com/53452-herbivores.html), although there are reports of locust cannibalism when other food is scarce, Song said. A locust can eat its own weight in plant matter each day, which is only about 0.07 ounces (2 grams). But the largest locust swarms, called plagues, can number in the billions and together, a plague of locusts can consume so much plant material that they erase several months of growth before moving on, resulting in long-term effects on the health and finances of entire regions. > > For example, a plague of desert locusts that originated in Western Africa in 2003 and lasted until 2005 affected 22 countries and reportedly wiped out over 80% of crops, according to a report from the [Food and Agriculture Organization of the United Nations](http://www.fao.org/ag/locusts/common/ecg/1913/en/DesertLocustEvalReportE.pdf). By the time the plague finally declined in early 2005, the total cost of damage control efforts had reached half a billion dollars. > > Locust plagues may last for years once they are in full swing, with multiple generations of swarming locusts. But the worst plagues are generally infrequent, and some species go decades between major population explosions. However, experts say this is an additional challenge for disaster preparedness because the threat of a locust swarm can seem less critical if it hasn't been an issue for many years. - [View Highlight](https://read.readwise.io/read/01fn7bfkp0qbc0zttj8yg2xf47) - [View Highlight](https://read.readwise.io/read/01fn7bdzbj8m3wjy03mkaghkmf) ### q6 locusts can be monitored for > Some locust species, like the desert locust, normally live in the wilderness, Cease said. Monitoring for small outbreaks of these locust populations can help keep the problems manageable by suppressing the locusts before their swarm grows to a size large enough to cause national or multinational disasters. > > Other locusts, such as the Sengalese grasshopper (*Oedaleus senegalensis*), may live in agricultural areas even when in the solitary phase. Careful land management, such as carefully selecting crops and how to grow them, and controlling nutrients in the soil can help discourage those locust swarms from forming, Cease said. This should be one of the jobs of [[Indigenous Mage]] and we should absolutely analogize to the people on their border. - [View Highlight](https://read.readwise.io/read/01fn7be7npfxwbvssc59e1ng0n) - [View Highlight](https://read.readwise.io/read/01fn7bff9jffsabx62f4fqztgg) ### q7 pesticides make locus plagues worse > Although their swarming behavior doesn't happen often, locusts are typically thought of as fearsome pests prone to causing [natural disasters](https://www.livescience.com/33316-top-10-deadliest-natural-disasters.html). And although locusts don't bite people, people bite them. Locusts are edible and several cuisines around the world include [locust recipes](http://www.fao.org/ag/locusts/oldsite/LOCFAQ.htm#q19), such as peanut-stuffed locusts in Cambodia. But because modern farmers may use pesticides to protect their crops from locusts, eating locusts can be unsafe as they may be carrying residue from those pesticides. - [View Highlight](https://read.readwise.io/read/01fn7bg2g6qhmv5cfy4xyt0kcn) If it wern't for the pesticides maybe the farmers could eat the locusts, and then the impacts of the plague would be lessened.