![SGR laying](https://upload.wikimedia.org/wikipedia/commons/f/f2/SGR_laying.jpg)
Locusts (derived from the
Vulgar Latin
Vulgar Latin, also known as Popular or Colloquial Latin, is the range of non-formal Register (sociolinguistics), registers of Latin spoken from the Crisis of the Roman Republic, Late Roman Republic onward. Through time, Vulgar Latin would evolve ...
''locusta'', meaning
grasshopper
Grasshoppers are a group of insects belonging to the suborder Caelifera. They are among what is possibly the most ancient living group of chewing herbivorous insects, dating back to the early Triassic around 250 million years ago.
Grasshopp ...
) are various
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
of short-horned
grasshopper
Grasshoppers are a group of insects belonging to the suborder Caelifera. They are among what is possibly the most ancient living group of chewing herbivorous insects, dating back to the early Triassic around 250 million years ago.
Grasshopp ...
s in the family
Acrididae
The AcrididaeMacLeay WS (1821) ''Horae Entomologicae or Essays on the Annulose Animals'' 2 are the predominant family of grasshoppers, comprising some 10,000 of the 11,000 species of the entire suborder Caelifera. The Acrididae are best known bec ...
that have a
swarming
Swarm behaviour, or swarming, is a collective behaviour exhibited by entities, particularly animals, of similar size which aggregate together, perhaps milling about the same spot or perhaps moving ''en masse'' or migrating in some direction. ...
phase. These insects are usually solitary, but under certain circumstances they become more abundant and change their behaviour and habits, becoming
gregarious
Sociality is the degree to which individuals in an animal population tend to associate in social groups (gregariousness) and form cooperative societies.
Sociality is a survival response to evolutionary pressures. For example, when a mother wasp ...
. No taxonomic distinction is made between locust and grasshopper species; the basis for the definition is whether a species forms swarms under intermittently suitable conditions; this has evolved independently in multiple lineages, comprising at least 18 genera in 5 different acridid subfamilies.
Normally, these grasshoppers are innocuous, their numbers are low, and they do not pose a major economic threat to agriculture. However, under suitable conditions of
drought
A drought is defined as drier than normal conditions.Douville, H., K. Raghavan, J. Renwick, R.P. Allan, P.A. Arias, M. Barlow, R. Cerezo-Mota, A. Cherchi, T.Y. Gan, J. Gergis, D. Jiang, A. Khan, W. Pokam Mba, D. Rosenfeld, J. Tierney, an ...
followed by rapid vegetation growth,
serotonin
Serotonin () or 5-hydroxytryptamine (5-HT) is a monoamine neurotransmitter. Its biological function is complex and multifaceted, modulating mood, cognition, reward, learning, memory, and numerous physiological processes such as vomiting and vas ...
in their brains triggers dramatic changes: they start to breed abundantly, becoming gregarious and nomadic (loosely described as
migratory) when their populations become dense enough. They form bands of wingless
nymphs
A nymph ( grc, νύμφη, nýmphē, el, script=Latn, nímfi, label=Modern Greek; , ) in ancient Greek folklore is a minor female nature deity. Different from Greek goddesses, nymphs are generally regarded as personifications of nature, are typ ...
that later become swarms of winged adults. Both the bands and the swarms move around, rapidly strip fields, and
damage crops. The adults are powerful fliers; they can travel great distances, consuming most of the green vegetation wherever the swarm settles.
Locusts have formed
plagues since
prehistory
Prehistory, also known as pre-literary history, is the period of human history between the use of the first stone tools by hominins 3.3 million years ago and the beginning of recorded history with the invention of writing systems. The use of ...
. The
ancient Egyptians carved them on their tombs and the insects are mentioned in the ''
Iliad
The ''Iliad'' (; grc, Ἰλιάς, Iliás, ; "a poem about Ilium") is one of two major ancient Greek epic poems attributed to Homer. It is one of the oldest extant works of literature still widely read by modern audiences. As with the ''Odysse ...
'', the
Mahabharata
The ''Mahābhārata'' ( ; sa, महाभारतम्, ', ) is one of the two major Sanskrit epics of ancient India in Hinduism, the other being the ''Rāmāyaṇa''. It narrates the struggle between two groups of cousins in the Kuruk ...
, and the
Bible
The Bible (from Koine Greek , , 'the books') is a collection of religious texts or scriptures that are held to be sacred in Christianity, Judaism, Samaritanism, and many other religions. The Bible is an anthologya compilation of texts of a ...
. Swarms have devastated crops and have caused
famine
A famine is a widespread scarcity of food, caused by several factors including war, natural disasters, crop failure, Demographic trap, population imbalance, widespread poverty, an Financial crisis, economic catastrophe or government policies. Th ...
s and human migrations. More recently, changes in
agricultural
Agriculture or farming is the practice of cultivating Plant, plants and livestock. Agriculture was the key development in the rise of Sedentism, sedentary human civilization, whereby farming of Domestication, domesticated species created food ...
practices and better surveillance of locust breeding grounds have allowed control measures at an early stage. Traditional locust control uses
insecticide
Insecticides are substances used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. Insecticides are used in agriculture, medicine, industry and by consumers. Insecticides are claimed to b ...
s from the ground or air, but newer
biological control
Biological control or biocontrol is a method of controlling pests, such as insects, mites, weeds, and plant diseases, using other organisms. It relies on predation, parasitism, herbivory, or other natural mechanisms, but typically also invo ...
methods are proving effective.
Swarming behaviour decreased in the 20th century, but despite modern surveillance and control methods, swarms can still form; when suitable weather conditions occur and vigilance lapses, plagues can occur.
Locusts are large insects and convenient for research and classroom study of zoology. They are
edible by humans. They have been eaten throughout history and are considered a
delicacy
A delicacy is usually a rare and expensive food item that is considered highly desirable, sophisticated, or peculiarly distinctive within a given culture. Irrespective of local preferences, such a label is typically pervasive throughout a r ...
in many countries.
Swarming grasshoppers
Locusts are the
swarming
Swarm behaviour, or swarming, is a collective behaviour exhibited by entities, particularly animals, of similar size which aggregate together, perhaps milling about the same spot or perhaps moving ''en masse'' or migrating in some direction. ...
phase of certain species of short-horned
grasshopper
Grasshoppers are a group of insects belonging to the suborder Caelifera. They are among what is possibly the most ancient living group of chewing herbivorous insects, dating back to the early Triassic around 250 million years ago.
Grasshopp ...
s in the family
Acrididae
The AcrididaeMacLeay WS (1821) ''Horae Entomologicae or Essays on the Annulose Animals'' 2 are the predominant family of grasshoppers, comprising some 10,000 of the 11,000 species of the entire suborder Caelifera. The Acrididae are best known bec ...
. These insects are usually solitary, but under certain circumstances become more abundant and change their behaviour and habits, becoming
gregarious
Sociality is the degree to which individuals in an animal population tend to associate in social groups (gregariousness) and form cooperative societies.
Sociality is a survival response to evolutionary pressures. For example, when a mother wasp ...
.
![Copulating desert locust pair](https://upload.wikimedia.org/wikipedia/commons/3/37/Copulating_desert_locust_pair.jpg)
No
taxonomic
Taxonomy is the practice and science of categorization or classification.
A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. ...
distinction is made between locust and grasshopper species; the basis for the definition is whether a species forms swarms under intermittently suitable conditions. In English, the term "locust" is used for grasshopper species that change
morphologically and behaviourally on crowding, forming swarms that develop from bands of immature stages called hoppers. The change is referred to in the technical literature as "density-dependent
phenotypic plasticity
Phenotypic plasticity refers to some of the changes in an organism's behavior, morphology and physiology in response to a unique environment. Fundamental to the way in which organisms cope with environmental variation, phenotypic plasticity encompa ...
".
These changes are examples of phase
polyphenism
A polyphenic trait is a trait for which multiple, discrete phenotypes can arise from a single genotype as a result of differing environmental conditions. It is therefore a special case of phenotypic plasticity.
There are several types of polyphen ...
; they were first analysed and described by
Boris Uvarov
Sir Boris Petrovitch Uvarov (3 November 1886 – 18 March 1970) was a Russian-British entomologist best known for his work on the biology and ecology of locusts. He has been called the father of acridology.
Biography
Boris Petrovitch Uvarov was ...
, who was instrumental in setting up the
Anti-Locust Research Centre The Anti-Locust Research Centre (ALRC) was set up in London, United Kingdom, by the Colonial Office in 1945, with the aim of improving the worldwide forecasting and control of locusts. The Russian-British entomologist Boris Uvarov was appointed as i ...
. He made his discoveries during his studies of the migratory locust in the
Caucasus
The Caucasus () or Caucasia (), is a region between the Black Sea and the Caspian Sea, mainly comprising Armenia, Azerbaijan, Georgia, and parts of Southern Russia. The Caucasus Mountains, including the Greater Caucasus range, have historically ...
, whose solitary and gregarious phases had previously been thought to be separate species (''Locusta migratoria'' and ''L. danica'' L.). He designated the two phases as ''solitaria'' and ''gregaria''.
These are also referred to as
statary and migratory
morph
Morph may refer to:
Biology
* Morph (zoology), a visual or behavioral difference between organisms of distinct populations in a species
* Muller's morphs, a classification scheme for genetic mutations
* "-morph", a suffix commonly used in tax ...
s, though strictly speaking, their swarms are
nomad
A nomad is a member of a community without fixed habitation who regularly moves to and from the same areas. Such groups include hunter-gatherers, pastoral nomads (owning livestock), tinkers and trader nomads. In the twentieth century, the popu ...
ic rather than
migratory.
Charles Valentine Riley
Charles Valentine Riley (18 September 1843 – 14 September 1895) was a British-born American entomologist and artist. He was one of the first individuals to use biological pest control and authored over 2,400 publications. He convinced Congress ...
and
Norman Criddle
Norman Criddle, born in 1875 in Addlestone, Surrey, England, died in 1933 in Winnipeg, Manitoba, Canada, was an entomologist active in the early development of control strategies for agriculturally important grasshoppers (Insecta: Orthoptera) in ...
were also involved in achieving the understanding and control of locusts.
Swarming behaviour is a response to overcrowding. Increased tactile stimulation of the hind legs causes an increase in levels of serotonin. This causes the locust to change colour, eat much more, and breed much more easily. The transformation of the locust to the swarming form is induced by several contacts per minute over a four-hour period. A large swarm can consist of billions of locusts spread out over an area of thousands of square kilometres, with a population of up to 80 million per square kilometre (200 million per square mile).
[ When desert locusts meet, their nervous systems release serotonin, which causes them to become mutually attracted, a prerequisite for swarming.
The initial bands of gregarious hoppers are known as "outbreaks", and when these join together into larger groups, the event is known as an "upsurge". Continuing agglomerations of upsurges on a regional level originating from a number of entirely separate breeding locations are known as "plagues".] During outbreaks and the early stages of upsurges, only part of the locust population becomes gregarious, with scattered bands of hoppers spread out over a large area. As time goes by, the insects become more cohesive and the bands become concentrated in a smaller area. In the desert locust plague in Africa, the Middle East, and Asia that lasted from 1966 to 1969, the number of locusts increased from two to 30 billion over two generations, but the area covered decreased from over to .[
]
Solitary and gregarious phases
One of the greatest differences between the solitary and gregarious phases is behavioural. The ''gregaria'' nymphs are attracted to each other, this being seen as early as the second instar
An instar (, from the Latin '' īnstar'', "form", "likeness") is a developmental stage of arthropods, such as insects, between each moult (''ecdysis''), until sexual maturity is reached. Arthropods must shed the exoskeleton in order to grow or ass ...
. They soon form bands of many thousands of individuals. These groups behave like cohesive units and move across the landscape, mostly downhill, but making their way around barriers and merging with other bands. The attraction between the insects involves visual and olfactory
The sense of smell, or olfaction, is the special sense through which smells (or odors) are perceived. The sense of smell has many functions, including detecting desirable foods, hazards, and pheromones, and plays a role in taste.
In humans, it ...
cues. The bands seem to navigate using the sun. They pause to feed at intervals before continuing on, and may cover tens of kilometres over a few weeks.[
Also, differences in morphology and development are seen. In the desert locust and the migratory locust, for example, the ''gregaria'' nymphs become darker with strongly contrasting yellow and black markings, they grow larger, and have a longer nymphal period; the adults are larger with different body proportions, less ]sexual dimorphism
Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...
, and higher metabolic rate
Metabolism (, from el, μεταβολή ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cell ...
s; they mature more rapidly and start reproducing earlier, but have lower levels of fecundity
Fecundity is defined in two ways; in human demography, it is the potential for reproduction of a recorded population as opposed to a sole organism, while in population biology, it is considered similar to fertility, the natural capability to pr ...
.[
The mutual attraction between individual insects continues into adulthood, and they continue to act as a cohesive group. Individuals that get detached from a swarm fly back into the mass. Others that get left behind after feeding take off to rejoin the swarm when it passes overhead. When individuals at the front of the swarm settle to feed, others fly past overhead and settle in their turn, the whole swarm acting like a rolling unit with an ever-changing leading edge. The locusts spend much time on the ground feeding and resting, moving on when the vegetation is exhausted. They may then fly a considerable distance before settling in a location where transitory rainfall has caused a green flush of new growth.][
]
Distribution and diversity
Several species of grasshopper
Grasshoppers are a group of insects belonging to the suborder Caelifera. They are among what is possibly the most ancient living group of chewing herbivorous insects, dating back to the early Triassic around 250 million years ago.
Grasshopp ...
s swarm as locusts in different parts of the world, on all continents except Antarctica: For example, the Australian plague locust
The Australian plague locust (''Chortoicetes terminifera'') is a native Australian insect in the family Acrididae, and a significant agricultural pest.
Adult Australian plague locusts range in size from 20 to 45 mm in length, and the colou ...
(''Chortoicetes terminifera'') swarms across Australia.[
The ]desert locust
The desert locust (''Schistocerca gregaria'') is a species of locust, a periodically swarming, short-horned grasshopper in the family Acrididae. They are found primarily in the deserts and dry areas of northern and eastern Africa, Arabia, and sou ...
(''Schistocerca gregaria'') is probably the best known species owing to its wide distribution (North Africa
North Africa, or Northern Africa is a region encompassing the northern portion of the African continent. There is no singularly accepted scope for the region, and it is sometimes defined as stretching from the Atlantic shores of Mauritania in ...
, Middle East
The Middle East ( ar, الشرق الأوسط, ISO 233: ) is a geopolitical region commonly encompassing Arabian Peninsula, Arabia (including the Arabian Peninsula and Bahrain), Anatolia, Asia Minor (Asian part of Turkey except Hatay Pro ...
, and Indian subcontinent
The Indian subcontinent is a list of the physiographic regions of the world, physiographical region in United Nations geoscheme for Asia#Southern Asia, Southern Asia. It is situated on the Indian Plate, projecting southwards into the Indian O ...
)[ and its ability to ]migrate
Migration, migratory, or migrate may refer to: Human migration
* Human migration, physical movement by humans from one region to another
** International migration, when peoples cross state boundaries and stay in the host state for some minimum le ...
over long distances. A major infestation covered much of western Africa from 2003 to 2005, after unusually heavy rain set up favourable ecological conditions for swarming. The first outbreaks occurred in Mauritania, Mali, Niger, and Sudan in 2003. The rain allowed swarms to develop and move north to Morocco and Algeria, threatening croplands. Swarms crossed Africa, appearing in Egypt, Jordan and Israel, the first time in those countries for 50 years. The cost of handling the infestation was put at US$122 million, and the damage to crops at up to $2.5 billion.
The migratory locust
The migratory locust (''Locusta migratoria'') is the most widespread locust species, and the only species in the genus ''Locusta''. It occurs throughout Africa, Asia, Australia and New Zealand. It used to be common in Europe but has now become ...
(''Locusta migratoria''), sometimes classified into up to 10 subspecies, swarms in Africa, Asia, Australia, and New Zealand, but has become rare in Europe. In 2013, the Madagascan form of the migratory locust formed many swarms of over a billion insects, reaching "plague" status and covering about half the country by March 2013.
Species such as the Senegalese grasshopper
The Senegalese grasshopper (''Oedaleus senegalensis'') is a medium-sized grasshopper species found in the Sahel region of Africa, the Canary Islands, Cape Verde Islands, and West Asia. Although not called a locust in English, this species show ...
(''Oedaleus senegalensis'') and the African rice grasshopper (''Hieroglyphus daganensis''), both from the Sahel
The Sahel (; ar, ساحل ' , "coast, shore") is a region in North Africa. It is defined as the ecoclimatic and biogeographic realm of transition between the Sahara to the north and the Sudanian savanna to the south. Having a hot semi-arid c ...
, often display locust-like behaviour and change morphologically on crowding.[
North America is currently the only sub-continent besides Antarctica without a native locust species. The ]Rocky Mountain locust
The Rocky Mountain locust (''Melanoplus spretus'') is an extinct species of grasshopper that ranged through the western half of the United States and some western portions of Canada with large numbers seen until the end of the 19th century. Sight ...
was formerly one of the most significant insect pests there, but it became extinct in 1902. In the 1930s, during the Dust Bowl
The Dust Bowl was a period of severe dust storms that greatly damaged the ecology and agriculture of the American and Canadian prairies during the 1930s. The phenomenon was caused by a combination of both natural factors (severe drought) an ...
, a second species of North American locust, the High Plains locust (''Dissosteira longipennis
''Dissosteira longipennis'', the high plains locust, is a species of band-winged grasshopper in the family Acrididae. It is found in North America. During the 1930s, it formed enormous swarms and caused significant damage to crops in the western ...
'') reached plague proportions in the American Midwest. Today, the High Plains locust is a rare species, leaving North America with no regularly swarming locusts.
Interaction with humans
Ancient times
Study of literature shows how pervasive plagues of locusts were over the course of history. The insects arrived unexpectedly, often after a change of wind direction or weather, and the consequences were devastating. The Ancient Egyptians carved locusts on tombs in the period 2470 to 2220 BC. A devastating plague in Egypt is also mentioned in the Book of Exodus
The Book of Exodus (from grc, Ἔξοδος, translit=Éxodos; he, שְׁמוֹת ''Šəmōṯ'', "Names") is the second book of the Bible. It narrates the story of the Exodus, in which the Israelites leave slavery in Biblical Egypt through t ...
in the Bible. The ''Iliad
The ''Iliad'' (; grc, Ἰλιάς, Iliás, ; "a poem about Ilium") is one of two major ancient Greek epic poems attributed to Homer. It is one of the oldest extant works of literature still widely read by modern audiences. As with the ''Odysse ...
'' mentions locusts taking to the wing to escape fire. Plagues of locusts are also mentioned in the Quran. In the ninth century BC, the Chinese authorities appointed anti-locust officers.[ In the ]New Testament
The New Testament grc, Ἡ Καινὴ Διαθήκη, transl. ; la, Novum Testamentum. (NT) is the second division of the Christian biblical canon. It discusses the teachings and person of Jesus, as well as events in first-century Christ ...
, John the Baptist was said to survive in the wilderness on locusts and wild honey; and human-headed locusts appear in the Book of Revelation
The Book of Revelation is the final book of the New Testament (and consequently the final book of the Christian Bible). Its title is derived from the first word of the Koine Greek text: , meaning "unveiling" or "revelation". The Book of R ...
.
Aristotle
Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of phil ...
studied locusts and their breeding habits and Livy
Titus Livius (; 59 BC – AD 17), known in English as Livy ( ), was a Ancient Rome, Roman historian. He wrote a monumental history of Rome and the Roman people, titled , covering the period from the earliest legends of Rome before the traditiona ...
recorded a devastating plague in Capua
Capua ( , ) is a city and ''comune'' in the province of Caserta, in the region of Campania, southern Italy, situated north of Naples, on the northeastern edge of the Campanian plain.
History
Ancient era
The name of Capua comes from the Etrusc ...
in 203 BC. He mentioned human epidemics following locust plagues which he associated with the stench from the putrifying corpses; the linking of human disease outbreaks to locust plagues was widespread. A pestilence in the northwestern provinces of China in 311 AD that killed 98% of the population locally was blamed on locusts, and may have been caused by an increase in numbers of rat
Rats are various medium-sized, long-tailed rodents. Species of rats are found throughout the order Rodentia, but stereotypical rats are found in the genus ''Rattus''. Other rat genera include ''Neotoma'' ( pack rats), ''Bandicota'' (bandicoot ...
s (and their flea
Flea, the common name for the order Siphonaptera, includes 2,500 species of small flightless insects that live as external parasites of mammals and birds. Fleas live by ingesting the blood of their hosts. Adult fleas grow to about long, a ...
s) that devoured the locust carcasses.
Recent times
During the last two millennia, desert locust plagues have appeared sporadically in Africa, the Middle East, and Europe. Other species of locusts caused havoc in North and South America, Asia, and Australasia; in China, 173 outbreaks over 1924 years.[ The ]Bombay locust
''Patanga succincta'', the Bombay locust, is a species of locust found in India and southeast Asia. Usually a solitary insect, only in India has it has exhibited swarming behaviour. The last plague of this locust was in that country between 1901 ...
(''Nomadacris succincta'') was a major pest in India and southeastern Asia in the 18th and 19th centuries, but has seldom swarmed since the last plague in 1908.
In the spring of 1747 locusts arrived outside Damascus
)), is an adjective which means "spacious".
, motto =
, image_flag = Flag of Damascus.svg
, image_seal = Emblem of Damascus.svg
, seal_type = Seal
, map_caption =
, ...
eating the majority of the crops and vegetation of the surrounding countryside. One local barber, Ahmad al-Budayri, recalled the locusts "came like a black cloud. They covered everything: the trees and the crops. May God Almighty save us!"
The extinction of the Rocky Mountain locust
The Rocky Mountain locust (''Melanoplus spretus'') is an extinct species of grasshopper that ranged through the western half of the United States and some western portions of Canada with large numbers seen until the end of the 19th century. Sight ...
has been a source of puzzlement. It had swarmed throughout the west of the United States and parts of Canada in the 19th century. Albert's swarm
Albert's swarm was an immense concentration of the Rocky Mountain locust that swarmed the Western United States in 1875. It was named after Albert Child, a physician interested in meteorology, who calculated the size of the swarm to by multiplying ...
of 1875 was estimated to cover (greater than the area of California
California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...
) and to weigh 27.5 million tons, with some 12.5 trillion insects. The last specimen was seen alive in Canada in 1902. Recent research suggests the breeding grounds of this insect in the valleys of the Rocky Mountains
The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch in straight-line distance from the northernmost part of western Canada, to New Mexico in ...
came under sustained agricultural development during the large influx of gold miners,[Encarta Reference Library Premium 2005 DVD. ''Rocky Mountain Locust''.] destroying the underground eggs of the locust.
The 1915 infestation across Palestine and Syria was one of the main contributors to famine in Lebanon which lasted from 1915 to 1918 during which around 200,000 people died.
Monitoring
Early intervention to prevent large locust swarms is more successful than later action once swarms have built up. The means to control locust populations is now available, but organisational, financial, and political problems may be difficult to overcome. Monitoring is the key to early detection and eradication. Ideally, a sufficient proportion of nomadic bands can be killed with insecticide before their swarming phase. This may be possible in richer countries like Morocco and Saudi Arabia, but neighbouring poorer countries such as Mauritania
Mauritania (; ar, موريتانيا, ', french: Mauritanie; Berber: ''Agawej'' or ''Cengit''; Pulaar: ''Moritani''; Wolof: ''Gànnaar''; Soninke:), officially the Islamic Republic of Mauritania ( ar, الجمهورية الإسلامية ...
and Yemen
Yemen (; ar, ٱلْيَمَن, al-Yaman), officially the Republic of Yemen,, ) is a country in Western Asia. It is situated on the southern end of the Arabian Peninsula, and borders Saudi Arabia to the Saudi Arabia–Yemen border, north and ...
lack the resources and may breed locust swarms that threaten the whole region.[
Several organisations around the world monitor the threat from locusts. They provide forecasts detailing regions likely to suffer from locust plagues in the near future. In Australia, this service is provided by the ]Australian Plague Locust Commission
The Australian Plague Locust Commission (APLC) is a joint venture of the Australian Government and the member states of New South Wales, Victoria, South Australia and Queensland, created in 1974 to manage outbreaks of the Australian plague locust, ...
. It has been very successful in dealing with developing outbreaks, but has the great advantage of having a defined area to monitor and defend without locust invasions from elsewhere. In Central and Southern Africa, the service is provided by the International Locust Control Organization for Central and Southern Africa. In West and Northwest Africa, the service is co-ordinated by the Food and Agriculture Organization
The Food and Agriculture Organization of the United Nations (FAO)french: link=no, Organisation des Nations unies pour l'alimentation et l'agriculture; it, Organizzazione delle Nazioni Unite per l'Alimentazione e l'Agricoltura is an intern ...
's Commission for Controlling the Desert Locust in the Western Region, and executed by locust control agencies belonging to each country concerned. The FAO also monitors the situation in the Caucasus and Central Asia, where over 25 million hectares of cultivated land are under threat. In February 2020, in an effort to end massive locust outbreaks, India decided to use drones and special equipment to monitor locusts and spray insecticides.
Control
Historically, people could do little to protect their crops from locusts, although eating the insects may have been some compensation. By the early 20th century, efforts were made to disrupt the development of the insects by cultivating the soil where eggs were laid, collecting hoppers with catching machines, killing them with flamethrowers, trapping them in ditches, and crushing them with rollers and other mechanical methods.[ By the 1950s, the ]organochloride
An organochloride, organochlorine compound, chlorocarbon, or chlorinated hydrocarbon is an organic compound containing at least one covalent bond, covalently bonded atom of chlorine. The chloroalkane class (alkanes with one or more hydrogens subst ...
dieldrin
Dieldrin is an organochloride originally produced in 1948 by J. Hyman & Co, Denver, as an insecticide. Dieldrin is closely related to aldrin, which reacts further to form dieldrin. Aldrin is not toxic to insects; it is oxidized in the insect to fo ...
was found to be an extremely effective insecticide, but it was later banned in most countries because of its persistence in the environment and its accumulation
Accumulation may refer to:
Finance
* Accumulation function, a mathematical function defined in terms of the ratio future value to present value
* Capital accumulation, the gathering of objects of value
Science and engineering
* Accumulate (highe ...
in the food chain
A food chain is a linear network of links in a food web starting from producer organisms (such as grass or algae which produce their own food via photosynthesis) and ending at an apex predator species (like grizzly bears or killer whales), det ...
.[
]
In years when locust control is needed, the hoppers are targeted early by applying water-based contact pesticide
Pesticides are substances that are meant to control pests. This includes herbicide, insecticide, nematicide, molluscicide, piscicide, avicide, rodenticide, bactericide, insect repellent, animal repellent, microbicide, fungicide, and lampri ...
s from tractor-based sprayers. This is effective but slow and labour-intensive; a preferable method is spraying concentrated insecticide from aircraft over the insects or vegetation. The use of ultralow-volume spraying of contact pesticides from aircraft in overlapping swathes is effective against nomadic bands and can be used to treat large areas of land swiftly.[ Other modern technologies for planning locust control include ]GPS
The Global Positioning System (GPS), originally Navstar GPS, is a Radionavigation-satellite service, satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of t ...
, GIS tools, and satellite imagery
Satellite images (also Earth observation imagery, spaceborne photography, or simply satellite photo) are images of Earth collected by imaging satellites operated by governments and businesses around the world. Satellite imaging companies sell ima ...
with rapid computer data management and analysis.
A biological pesticide
A Biopesticide is a biological substance or organism that damages, kills, or repels organisms seens as pests. Biological pest management intervention involves predatory, parasitic, or chemical relationships.
They are obtained from organisms inclu ...
to control locusts was tested across Africa by a multinational team in 1997. Dried fungal spores of a ''Metarhizium acridum
''Metarhizium acridum''
is the new name given to a group of fungal isolates that are known to be virulent and specific to the Acrididea (grasshoppers). Previously, this species has had variety status in ''Metarhizium anisopliae'' (var. ''acridu ...
'' sprayed in breeding areas pierce the locust exoskeleton on germination and invade the body cavity, causing death. The fungus is passed from insect to insect and persists in the area, making repeated treatments unnecessary. This approach to locust control was used in Tanzania in 2009 to treat around 10,000 hectares in the Iku-Katavi National Park infested with adult locusts. The outbreak was contained without harm to the local elephant
Elephants are the largest existing land animals. Three living species are currently recognised: the African bush elephant, the African forest elephant, and the Asian elephant. They are the only surviving members of the family Elephantidae an ...
s, hippopotamus
The hippopotamus ( ; : hippopotamuses or hippopotami; ''Hippopotamus amphibius''), also called the hippo, common hippopotamus, or river hippopotamus, is a large semiaquatic mammal native to sub-Saharan Africa. It is one of only two extan ...
es, and giraffe
The giraffe is a large African hoofed mammal belonging to the genus ''Giraffa''. It is the tallest living terrestrial animal and the largest ruminant on Earth. Traditionally, giraffes were thought to be one species, ''Giraffa camelopardalis ...
s.[
The ideal in locust control is preventive and proactive methods that disrupt the environment as little as possible, to make agricultural production more secure.][
]
As experimental models
The locust is large and easy to breed and rear, and is used as an experimental model in research studies. It has been used in evolutionary biology research and to test the generalizability of conclusions reached about test organisms such as the fruit fly (''Drosophila'') and the housefly
The housefly (''Musca domestica'') is a fly of the suborder Cyclorrhapha. It is believed to have evolved in the Cenozoic Era, possibly in the Middle East, and has spread all over the world as a commensal of humans. It is the most common fl ...
(''Musca''). It is a suitable school laboratory animal because of its robustness and ease of breeding and handling.
As food
Locusts have been used as food throughout history. They are considered meat. Several cultures throughout the world consume insects, and locusts are considered a delicacy in many African, Middle Eastern, and Asian countries.
They can be cooked in many ways, but are often fried, smoked, or dried.
The Bible records that John the Baptist
John the Baptist or , , or , ;Wetterau, Bruce. ''World history''. New York: Henry Holt and Company. 1994. syc, ܝܘܿܚܲܢܵܢ ܡܲܥܡܕ݂ܵܢܵܐ, Yoḥanān Maʿmḏānā; he, יוחנן המטביל, Yohanān HaMatbil; la, Ioannes Bapti ...
ate locusts and wild honey ( el, ἀκρίδες καὶ μέλι ἄγριον, akrides kai meli agrion) while living in the wilderness. Attempts have been made to explain the text to mean ascetic
Asceticism (; from the el, ἄσκησις, áskesis, exercise', 'training) is a lifestyle characterized by abstinence from sensual pleasures, often for the purpose of pursuing spiritual goals. Ascetics may withdraw from the world for their p ...
vegetarian
Vegetarianism is the practice of abstaining from the consumption of meat (red meat, poultry, seafood, insects, and the flesh of any other animal). It may also include abstaining from eating all by-products of animal slaughter.
Vegetarianism m ...
food such as carob beans, but the plain meaning of ''akrides'' is locust.
The Torah
The Torah (; hbo, ''Tōrā'', "Instruction", "Teaching" or "Law") is the compilation of the first five books of the Hebrew Bible, namely the books of Genesis, Exodus, Leviticus, Numbers and Deuteronomy. In that sense, Torah means the s ...
, although disallowing the use of most insects as food, permits the consumption of certain locusts; specifically, the red, the yellow, the spotted grey, and the white are permissible. Islamic jurisprudence
''Fiqh'' (; ar, فقه ) is Islamic jurisprudence. Muhammad-> Companions-> Followers-> Fiqh.
The commands and prohibitions chosen by God were revealed through the agency of the Prophet in both the Quran and the Sunnah (words, deeds, and e ...
deems eating locusts to be halal
''Halal'' (; ar, حلال, ) is an Arabic word that translates to "permissible" in English. In the Quran, the word ''halal'' is contrasted with ''haram'' (forbidden). This binary opposition was elaborated into a more complex classification kno ...
.[ The Prophet ]Muhammad
Muhammad ( ar, مُحَمَّد; 570 – 8 June 632 Common Era, CE) was an Arab religious, social, and political leader and the founder of Islam. According to Muhammad in Islam, Islamic doctrine, he was a prophet Divine inspiration, di ...
was reported to have eaten locusts during a military raid with his companions.
Locusts are eaten in the Arabian Peninsula
The Arabian Peninsula, (; ar, شِبْهُ الْجَزِيرَةِ الْعَرَبِيَّة, , "Arabian Peninsula" or , , "Island of the Arabs") or Arabia, is a peninsula of Western Asia, situated northeast of Africa on the Arabian Plate ...
, including Saudi Arabia. In 2014, consumption of locusts spiked around Ramadan
, type = islam
, longtype = Religious
, image = Ramadan montage.jpg
, caption=From top, left to right: A crescent moon over Sarıçam, Turkey, marking the beginning of the Islamic month of Ramadan. Ramadan Quran reading in Bandar Torkaman, Iran. ...
especially in the Al-Qassim Region
The Qassim Province ( ar, منطقة القصيم ' , Najdi Arabic: ), also known as the Qassim Region, is one of the 13 provinces of Saudi Arabia. Located at the heart of the country near the geographic center of the Arabian Peninsula, it has ...
, since many Saudis believe they are healthy to eat, but the Saudi Ministry of Health warned that pesticides made them unsafe. Yemenis
Yemenis or Yemenites ( ar, يمنيون) are the nationals of Yemen.
Social hierarchy
There is a system of social stratification in Yemen that was officially abolished at the creation of the Republic of Yemen in 1962 but, in practice, this syst ...
also consume locusts, and expressed discontent over governmental plans to use pesticides against them. ʻAbd al-Salâm Shabînî described a locust recipe from Morocco. 19th century European travellers observed Arabs in Arabia, Egypt, and Morocco selling, cooking, and eating locusts. They reported that in Egypt and Palestine locusts were consumed. They reported that in Palestine, around the River Jordan, in Egypt, in Arabia, and in Morocco that Arabs ate locusts, while Syrian peasants did not eat locusts.
In the Haouran region, Fellah
A fellah ( ar, فَلَّاح ; feminine ; plural ''fellaheen'' or ''fellahin'', , ) is a peasant, usually a farmer or agricultural laborer in the Middle East and North Africa. The word derives from the Arabic word for "ploughman" or "tiller". ...
s who were in poverty and suffered from famine ate locusts after removing the guts and head, while locusts were swallowed whole by Bedouins. Syrians, Copts, Greeks, Armenians, and other Christians and Arabs themselves reported that in Arabia locusts were eaten frequently and one Arab described to a European traveler the different types of locusts which were favored as food by Arabs. Persians use the Anti-Arab
Anti-Arabism, Anti-Arab sentiment, or Arabophobia includes opposition to, dislike, fear, or hatred of Arab people.
Historically, anti-Arab prejudice has been an issue in such events as the reconquest of the Iberian Peninsula, the condemnati ...
racial slur ''Arabe malakh-khor'' ( fa, عرب ملخ خور, literally "Arab locust eater") against Arabs.[ ]
Locusts yield about five times more edible protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...
per unit of fodder
Fodder (), also called provender (), is any agriculture, agricultural foodstuff used specifically to feed domesticated livestock, such as cattle, domestic rabbit, rabbits, sheep, horses, chickens and pigs. "Fodder" refers particularly to food g ...
than cattle, and produce lower levels of greenhouse gas
A greenhouse gas (GHG or GhG) is a gas that Absorption (electromagnetic radiation), absorbs and Emission (electromagnetic radiation), emits radiant energy within the thermal infrared range, causing the greenhouse effect. The primary greenhouse ...
es in the process. The feed conversion rate
In animal husbandry, feed conversion ratio (FCR) or feed conversion rate is a ratio or rate measuring of the efficiency with which the bodies of livestock convert animal feed into the desired output. For dairy cows, for example, the output is ...
of orthopterans is 1.7 kg/kg, while for beef it is typically about 10 kg/kg. The protein content in fresh weight is between 13 and 28 g / 100 g for adult locust, 14–18 g / 100 g for larvae, as compared to 19–26 g / 100 g for beef. The calculated protein efficiency ratio Protein efficiency ratio (PER) is based on the weight gain of a test subject divided by its intake of a particular food protein during the test period.
From 1919 until very recently, the PER had been a widely used method for evaluating the quality ...
is low, with 1.69 for locust protein compared to 2.5 for standard casein.[ A serving of 100 g of desert locust provides 11.5 g of fat, 53.5% of which is unsaturated, and 286 mg of cholesterol.] Among the fatty acids, palmitoleic, oleic, and linolenic acids were found to be the most abundant. Varying amounts of potassium, sodium, phosphorus, calcium, magnesium, iron, and zinc were present.[
]
See also
* List of locust swarms Locust swarms
Locusts (derived from the Vulgar Latin ''locusta'', meaning grasshopper) are various species of short-horned grasshoppers in the family Acrididae that have a swarming phase. These insects are usually solitary, but under certa ...
* Australian Plague Locust Commission
The Australian Plague Locust Commission (APLC) is a joint venture of the Australian Government and the member states of New South Wales, Victoria, South Australia and Queensland, created in 1974 to manage outbreaks of the Australian plague locust, ...
* LUBILOSA
LUBILOSA was the name of a research programme that aimed at developing a biological alternative to the chemical control of locusts. This name is an acronym of the French title of the programme: Lutte Biologique contre les Locustes et les Sauter ...
– Locust research programme
Notes
References
External links
Visual neuron of the locust
Ri Channel video, October 2011
FAO EMPRES
eLocust3M android app
Desert Locust Meteorological Monitoring at Sahel Resources
Locust Video
USAID Supplemental Environmental Assessment of the Eritrean Locust Control Program
USAID Supplemental Environmental Assessment: Pakistan Locust Control Programs, August 1993
*
{{Authority control
Biological hazards
Edible insects
Insect rearing
Insects in culture
Insect common names