Rocky Mountain locust
Encyclopedia
The Rocky Mountain locust (Melanoplus spretus) was the locust
species
that ranged through almost the entire western half of the United States
(and some western portions of Canada
) until the end of the 19th century. Sightings often placed their swarms in numbers far larger than any other species of locust, with one famed sighting
having been estimated at 198,000 square miles (513,000 km²) in size (greater than the area of California
), weighing 27.5 million tons, and consisting of some 12.5 trillion insects - the greatest concentration of animals ever recorded, according to The Guinness Book of Records.
But less than 30 years later, the species was apparently extinct, with the last recorded sighting of a live specimen in 1902 in southern Canada
. And because no one expected such a ubiquitous creature to become extinct, very few samples were ever collected (though a few preserved remains have been found in Grasshopper Glacier
, Montana
). Though grasshoppers still cause significant crop damage today, their populations do not even approach the densities of true locusts. Had the Rocky Mountain locust continued to survive, North American agriculture
would likely have had to adapt to its presence (North America is the only continent
without a major locust outside of Antarctica).
areas, though they existed on both sides of the Rocky Mountains
. Breeding in sandy areas and thriving in hot and dry conditions, they were often guaranteed a good food supply by prairie plants concentrating sugar
s in their stalks in times of drought. Movement of the locusts was probably assisted by a low-level jet stream
that persists through much of central North America
.
, Kansas
, Minnesota
, Missouri
, Nebraska
, and other states. The cause of their extinction is disputed, though it is possible that the plowing and irrigation
by settlers disrupted the natural life cycle of the insects by disturbing the sandy riverbeds that locusts would use for breeding. Reports from this era state that farmers brought up thousands of egg cases while plowing.
Because locusts are a form of grasshopper
that appear when grasshopper populations reach high densities, it was theorized that M. spretus might not be extinct; "solitary phase" individuals of the migratory grasshopper might be able to turn into the Rocky Mountain locust given the right conditions, however breeding experiments using many grasshopper species
in high-density environments have attempted to invoke the famous insect without success. Analysis of mitochondrial DNA
from museum specimens and related species suggests that the Rocky Mountain locust may have been a distinct and now extinct species, possibly closely related to the Bruner spurthroat grasshopper (Melanoplus
bruneri).
by Laura Ingalls Wilder
and Rose Wilder Lane
.
Locust
Locusts are the swarming phase of short-horned grasshoppers of the family Acrididae. These are species that can breed rapidly under suitable conditions and subsequently become gregarious and migratory...
species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
that ranged through almost the entire western half of the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
(and some western portions of Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
) until the end of the 19th century. Sightings often placed their swarms in numbers far larger than any other species of locust, with one famed sighting
Albert's swarm
Albert's swarm was an immense concentration of the Rocky Mountain locust that in 1875 swarmed the Western United States. It was named after Albert Child, a physician interested in meteorology, who calculated the size of the swarm to by multiplying the swarm's estimated speed with the time it took...
having been estimated at 198,000 square miles (513,000 km²) in size (greater than the area of California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
), weighing 27.5 million tons, and consisting of some 12.5 trillion insects - the greatest concentration of animals ever recorded, according to The Guinness Book of Records.
But less than 30 years later, the species was apparently extinct, with the last recorded sighting of a live specimen in 1902 in southern Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
. And because no one expected such a ubiquitous creature to become extinct, very few samples were ever collected (though a few preserved remains have been found in Grasshopper Glacier
Grasshopper Glacier (Montana)
Grasshopper Glacier is a glacier located in the Beartooth Mountains, Custer National Forest, Montana, U.S.. The glacier is within the Absaroka-Beartooth Wilderness, a part of the Greater Yellowstone Ecosystem. The glacier is approximately long and wide...
, Montana
Montana
Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...
). Though grasshoppers still cause significant crop damage today, their populations do not even approach the densities of true locusts. Had the Rocky Mountain locust continued to survive, North American agriculture
Agriculture
Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...
would likely have had to adapt to its presence (North America is the only continent
Continent
A continent is one of several very large landmasses on Earth. They are generally identified by convention rather than any strict criteria, with seven regions commonly regarded as continents—they are : Asia, Africa, North America, South America, Antarctica, Europe, and Australia.Plate tectonics is...
without a major locust outside of Antarctica).
Distribution
The locust largely afflicted prairiePrairie
Prairies are considered part of the temperate grasslands, savannas, and shrublands biome by ecologists, based on similar temperate climates, moderate rainfall, and grasses, herbs, and shrubs, rather than trees, as the dominant vegetation type...
areas, though they existed on both sides of the Rocky Mountains
Rocky Mountains
The Rocky Mountains are a major mountain range in western North America. The Rocky Mountains stretch more than from the northernmost part of British Columbia, in western Canada, to New Mexico, in the southwestern United States...
. Breeding in sandy areas and thriving in hot and dry conditions, they were often guaranteed a good food supply by prairie plants concentrating sugar
Sugar
Sugar is a class of edible crystalline carbohydrates, mainly sucrose, lactose, and fructose, characterized by a sweet flavor.Sucrose in its refined form primarily comes from sugar cane and sugar beet...
s in their stalks in times of drought. Movement of the locusts was probably assisted by a low-level jet stream
Jet stream
Jet streams are fast flowing, narrow air currents found in the atmospheres of some planets, including Earth. The main jet streams are located near the tropopause, the transition between the troposphere and the stratosphere . The major jet streams on Earth are westerly winds...
that persists through much of central North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
.
Extinction
The last major swarms of Rocky Mountain locust were between 1873 and 1877, when the locust caused $200 million in crop damage in ColoradoColorado
Colorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...
, Kansas
Kansas
Kansas is a US state located in the Midwestern United States. It is named after the Kansas River which flows through it, which in turn was named after the Kansa Native American tribe, which inhabited the area. The tribe's name is often said to mean "people of the wind" or "people of the south...
, Minnesota
Minnesota
Minnesota is a U.S. state located in the Midwestern United States. The twelfth largest state of the U.S., it is the twenty-first most populous, with 5.3 million residents. Minnesota was carved out of the eastern half of the Minnesota Territory and admitted to the Union as the thirty-second state...
, Missouri
Missouri
Missouri is a US state located in the Midwestern United States, bordered by Iowa, Illinois, Kentucky, Tennessee, Arkansas, Oklahoma, Kansas and Nebraska. With a 2010 population of 5,988,927, Missouri is the 18th most populous state in the nation and the fifth most populous in the Midwest. It...
, Nebraska
Nebraska
Nebraska is a state on the Great Plains of the Midwestern United States. The state's capital is Lincoln and its largest city is Omaha, on the Missouri River....
, and other states. The cause of their extinction is disputed, though it is possible that the plowing and irrigation
Irrigation
Irrigation may be defined as the science of artificial application of water to the land or soil. It is used to assist in the growing of agricultural crops, maintenance of landscapes, and revegetation of disturbed soils in dry areas and during periods of inadequate rainfall...
by settlers disrupted the natural life cycle of the insects by disturbing the sandy riverbeds that locusts would use for breeding. Reports from this era state that farmers brought up thousands of egg cases while plowing.
Because locusts are a form of grasshopper
Grasshopper
The grasshopper is an insect of the suborder Caelifera in the order Orthoptera. To distinguish it from bush crickets or katydids, it is sometimes referred to as the short-horned grasshopper...
that appear when grasshopper populations reach high densities, it was theorized that M. spretus might not be extinct; "solitary phase" individuals of the migratory grasshopper might be able to turn into the Rocky Mountain locust given the right conditions, however breeding experiments using many grasshopper species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
in high-density environments have attempted to invoke the famous insect without success. Analysis of mitochondrial DNA
Mitochondrial DNA
Mitochondrial DNA is the DNA located in organelles called mitochondria, structures within eukaryotic cells that convert the chemical energy from food into a form that cells can use, adenosine triphosphate...
from museum specimens and related species suggests that the Rocky Mountain locust may have been a distinct and now extinct species, possibly closely related to the Bruner spurthroat grasshopper (Melanoplus
Melanoplus
Melanoplus is a large genus of grasshoppers. They are the typical large grasshoppers in North America...
bruneri).
In fiction
A fictionalized description of the migration of Rocky Mountain locusts in the 1870s can be found in On the Banks of Plum CreekOn the Banks of Plum Creek
On the Banks of Plum Creek is a children's book written in 1937 by Laura Ingalls Wilder. The fourth of nine books written in her Little House series, it is based on Laura's childhood at Plum Creek near Walnut Grove, Minnesota in late 19th Century....
by Laura Ingalls Wilder
Laura Ingalls Wilder
Laura Elizabeth Ingalls Wilder was an American author who wrote the Little House series of books based on her childhood in a pioneer family...
and Rose Wilder Lane
Rose Wilder Lane
Rose Wilder Lane was an American journalist, travel writer, novelist, and political theorist...
.