Mormon crickets are insects known for their large swarms and voracious appetites. Their common name stems from a unique historical interaction with early settlers in western North America. This article explores their biology, historical impact, and ecological role.
The Name’s Origin Story
The common name “Mormon cricket” originates from a specific historical event in the mid-19th century. In 1848, early Mormon settlers in the Salt Lake Valley planted their first significant crops. These crops faced a devastating invasion of large, flightless insects that threatened to destroy the entire harvest and jeopardize the nascent settlements. This severe conflict led to the insects being dubbed “Mormon crickets,” a name firmly established due to the widespread impact of these infestations. While not true crickets, their encounters with these settlers cemented their common designation.
What Are Mormon Crickets?
Despite their common name, Mormon crickets (Anabrus simplex) are not true crickets; they are a species of shield-backed katydid. These large insects, with females measuring 5 to 7.5 centimeters (2 to 3 inches), have robust bodies covered by a shiny exoskeleton that varies in color. They possess long antennae and strong hind legs. Although they have vestigial wings, a shield-like structure on their thorax renders them flightless. Mormon crickets inhabit open grasslands, sagebrush, and desert regions across western North America, thriving in arid and semi-arid conditions. Their life cycle involves eggs laid in the soil, which hatch into nymphs that undergo seven developmental stages before reaching adulthood, a process taking 60 to 90 days.
Their Historic Confrontations with Settlers
The historical interactions between Mormon crickets and early settlers in the American West are significant. In 1848, a severe infestation descended upon the freshly planted fields of Mormon pioneers in the Salt Lake Valley. This event, often referred to as the “Cricket War of 1848,” threatened to decimate the settlers’ vital crops, creating widespread despair. As the pioneers struggled to protect their harvest, seagulls arrived in the valley and began preying on the crickets. These birds consumed the insects in vast quantities, regurgitating indigestible parts before returning for more. This intervention, which occurred over approximately two weeks, was seen by the settlers as a miraculous deliverance, leading to the event being known as the “Miracle of the Gulls.” While the gulls helped mitigate the damage, the crickets continued to be a problem. This historical episode is commemorated by a monument in Salt Lake City.
Their Ecological Role and Unique Habits
Mormon crickets play a role in the ecosystems of western North America, primarily as herbivores. They feed on a wide variety of plants, including forbs, grasses, and shrubs like sagebrush. While they are primarily plant eaters, they are also opportunistic omnivores, known to consume dead insects and even engage in cannibalism, particularly when food resources are scarce. This cannibalistic behavior can be driven by a need for protein and salt.
One of their most distinctive behaviors is their tendency to form large, migratory bands or swarms. These swarms can consist of millions of individuals and may travel up to 2 kilometers (1.25 miles) per day, sometimes covering distances of 50 miles in a season. The mass movement of these flightless insects can cause significant damage to vegetation and agricultural crops in their path.
Their outbreaks can last for several years, influencing nutrient cycling and potentially contributing to soil erosion in affected rangelands. They serve as a food source for various predators, including birds, rodents, and other insects.