Where grasshopper lay eggs questions

Where grasshopper lay eggs questions

All grasshoppers begin their lives as eggs. Yet eggs represent the least known stage of the grasshopper life cycle. They are laid in the soil of the habitat and develop hidden from the view of humans. Eggs of a few species, however, have been studied in both field and laboratory (Fig. 9).

Figure 9. One intact and one broken egg pod, exposing the eggs of the migratory grasshopper, Melanoplus sanguinipes (Fabricius).

Incubation of eggs begins immediately after females deposit them in the soil. The embryo, at first a tiny disc of cells laying on the ventral side of the yolk surface and at the posterior end of the eggs (Fig. 10), grows rapidly, receiving nourishment from the nutrient stores in the yolk.

From left to right: Stage 1 (5%) Stage 3 (10%) Stage 7 (20%) Stage 10 (30%) Stage 12 (40%) Stage 19 (50%)

Figure 10. Selected stages in the development of a grasshopper embryo (Melaoplus sanguinipes) held at a constant temperature of 30 C. Left two figures show whole egg; other figures show embryos removed from egg. (Illustrations adapted from Riegert, 1961; stages idetified and designated for embryos of Aulocara elliotti by Saralee Visscher, 1966).

In seven days the embryo of the migratory grasshopper, Melanoplus sanguinipes , held at an incubation temperature of 30Β½C, reaches Stage 19. In this stage the embryos of many rangeland species such as Aulocara elliotti and Camnula pellucida cease growth and begin a diapause . The embryo of the migratory grasshopper, however, continues to develop and at Stage 20 actively moves from the ventral to the dorsal surface and revolves 180Β½ on its long axis (see Figure 10, Stage 20). After 15 days the embryo has grown to Stage 24, having achieved 80 percent of its development. It then ceases growth and enters diapause. The embryo of the twostriped grasshopper, and probably others also, enter diapause at this stage. Exposed to favorable incubation temperatures, the eggs of a few rangeland species, such as Arphia conspersa and Xanthippus corallipes , develop completely and hatch during the same summer they are laid. The immediate cause of cessation of embryonic growth (diapause) in eggs of the majority of rangeland grasshoppers appears to be the shutdown of growth hormones. The embryos remain physiologically active as transfer of nutrient materials from the yolk into the embryonic fat body and other tissues continues. Cold temperatures of winter, however, slow or end this process and embryos enter a dormant period.

For eggs laid in temperate regions to reach their maximum development before diapause, they must receive sufficient heat, usually measured as day-degrees of heat accumulated in the soil at egg depth. Eggs deposited late in the season or during a cold summer may not receive this amount of heat, especially in northern areas such as the Canadian provinces of Alberta, Manitoba, and Saskatchewan. Eggs that do not reach their potential stage of development have reduced hatchability the following spring and thus do not contribute as much to the maintenance of a population.

During winter, low ground temperatures eventually break egg diapause. As soon as the ground warms above threshold soil temperatures of 50 to 55Β½F in spring, the embryos are ready to continue their development. Research has shown that for the few species studied, eggs need 400 day-degrees by fall to attain maximum embryonic growth and another 150 day-degrees in spring to initiate hatching. For completion of embryonic growth from start to finish, eggs require totals of 500 to 600 day-degrees.

In spring the emergence of hatching grasshoppers may be readily observed. All embryos of a single pod usually wriggle out one after another within several minutes. Once out, they immediately shed an embryonic membrane called the serosa. An individual hatchling, lying on its side or back and squirming, takes only a few minutes to free itself (Fig. 11). During this time the hatchlings are susceptible to predation by ants. After the shedding of the membrane the young grasshoppers stand upright and are able to jump away and escape attacking predators. In spring, young grasshoppers have available green and nutritious host plants. The majority of individuals in grasslands are grass feeders, but individuals of some species are mixed feeders, eating both grasses and forbs. Others are strictly forb feeders.

Figure 11. The lifecycle of the bigheaded grasshopper, Alucara ellliotti (Thomas). During summer in bare spots of grassland the female deposits at intervals batches of eggs. As soon as the eggs are laid, they begin embryonic development and reach an advanced stage in which they enter diapause and pass the winter. In spring the eggs complete embryonic devlopment and hatch. The young grasshopper sheds a serosal skin, the exoskeleton hardens, and the nymph begins to feed and grow. After molting five times and developing through five instars in 30-40 days, it becomes an adult grasshopper with functional wings. The adult female matures groups of six to eight eggs at a time and deposits them in the soil at intervwls of three to four days for the duration of her short life.

As insects grow and develop, they molt at intervals, changing structures and their form. This process is called metamorphosis . A number of insects undergo gradual (simple) metamorphosis, such as grasshoppers. With this type of metamorphosis the insect that hatches looks like the adult except for its smaller size, lack of wings, fewer antennal segments, and rudimentary genitalia (Fig. 11). Other insects with gradual metamorphosis include the true bugs, aphids, leafhoppers, crickets, and cockroaches. The majority of insects undergo complete (complex) metamorphosis, as the eggs hatch into wormlike larvae adapted for feeding and have a vastly different appearance from that of the adult insect. Before full-grown larvae can become adult insects they must enter into the pupal stage. In this stage they develop and grow the adult structures. Common examples of insects that undergo complete metamorphosis are beetles, butterflies, bees, wasps, and flies.

For young grasshoppers to continue their growth and development and reach the adult stage, they must periodically molt or shed their outer skin (Fig. 11). Depending on species and sex, they molt four to six times during their nymphal or immature life. The insect between molts is referred to as an instar; a species with five molts thus has five instars. After shedding the serosal skin, the newly hatched nymph is the first instar. After each molt the instar increases by one so that the nymph consecutively becomes a second, third, fourth, and fifth instar. When the fifth instar molts, the grasshopper becomes an adult or an imago.

The new adult has fully functional wings but is not yet ready to reproduce. The female has a preoviposition period of one to two weeks during which she increases in weight and matures the first batch of eggs. Having mated with a male of her species, the female digs a small hole in the soil with her ovipositor and deposits the first group of eggs. Once egg laying begins, the female continues to deposit eggs regularly for the rest of her short life. Depending on the species, production may range from three pods per week to one pod every one to two weeks. The species that lay fewer eggs per pod oviposit more often than those that lay more eggs per pod.

The egg pods of grasshoppers vary not only in the number of eggs they contain but also in their size, shape, and structure. Based on structure, four types have been recognized. In type I a stout pod forms from frothy glue and soil surrounding the eggs; froth is lacking between the eggs. In type II a weaker pod is formed from frothy glue between and surrounding the eggs. In type III frothy glue is present between the eggs but does not completely surround them. In type IV only a small amount of froth is secreted on the last eggs of a clutch, and most of the eggs lie loosely in the soil. Grasshopper eggs themselves vary in size, color, and shell sculpturing. Depending on the species eggs range from 4 to 9 mm long and may be white, yellow, olive, tan, brownish red, or dark brown. Eggs of certain species are two-toned brown and tan.

Events in the life cycle of an individual species of grasshopper β€” hatching, nymphal development, and adulthood β€” occur over extended periods. The eggs may hatch over a period of three to four weeks. Nymphs may be present in the habitat eight to ten weeks and adults nine to 11 weeks. Because of the overlapping of stages and instars, raw field data obtained by sampling populations do not answer several important questions. For example, how many eggs hatched? How many individuals molted successfully to the next instar? What was the average duration of each instar? How many became adults? What was the average length of life and the average fecundity of adult females? To obtain answers to these questions, detailed sampling data must be treated mathematically.

Laboratory data may also be used in studying grasshopper life histories. Table 4 provides information on the life history of the migratory grasshopper, Melanoplus sanguinipes , reared at a constant temperature of 86Β½F and 30-35% relative humidity and fed a nutritious diet of dry feed, green wheat, and dandelion leaves. The entire nymphal period averages 25 days for males and 30 days for females. Each instar takes four to five days to complete development except for the last instar, which takes seven days. Adult longevity of males averages 51 days and females, 52 days. Longevity of adults in the field is no doubt briefer because of the natural predators and parasites cutting short the lives of their prey.

TABLE 4. Life history of the migratory grasshopper, Melanoplus sanguinipes, reared in the laboratory at a constant temperature of 86.5 F.

www.uwyo.edu

Where grasshopper lay eggs questions

JULY-AUGUST 2003
Texas Cooperative Extension, Texas A&M University, College Station, Texas

Grasshoppers: Frequently Asked Questions, 2003

Dr. Allen Knutson,
Professor & Extension Entomologist, Texas Cooperative Extension

hy are grasshoppers so bad this year, again? Consecutive years of hot, dry summers and warm, dry autumns favor grasshopper survival and reproduction. Warm, dry fall weather allows grasshoppers more time to feed and lay eggs. The large numbers of grasshoppers present last fall left many eggs in the soil which hatched this spring. Also, rains in the spring when eggs are hatching drown young hoppers. Thus, dry weather in the spring favors their survival.

Grasshopper, Brachystala magna

Where do grasshoppers come from?
Grasshopper eggs are deposited in the soil l/2 – 2 inches deep in weedy areas, fencerows, ditches and hay fields. The eggs hatch in the spring and early summer. Eggs of different grasshopper species hatch out at different times, so young grasshoppers can be seen throughout the spring and early summer. Young grasshoppers, called nymphs, feed for about six weeks. Once nymphs reach the adult stage, they can fly. As weedy plants are consumed or dry in the summer heat, adult grasshoppers can fly from weedy areas and pastures to more succulent crops and landscapes.

When will grasshopper numbers decrease this season?
Although grasshoppers complete only one generation a year, eggs hatch over a long period of time. Development from egg to adult requires about 40-60 days. Also, eggs of different species hatch at different times so small grashoppers can be found throughout the growing season. Grasshopper can persist until late fall when old adults begin to die or when a killing frost occurs.

What can be done to reduce their numbers?
Weed control. Eliminating weeds will starve young hoppers and later discourage adults from laying eggs in the area. Destroying weeds infested with large numbers of grasshoppers can force the hungry grasshoppers to move to nearby crops or landscapes. Control the grasshoppers in the weedy area first with insecticides or be ready to protect nearby crops if they become infested. Grasshoppers deposit their eggs in undisturbed soil, as in fallow fields, road banks, and fence rows. Shallow tillage of the soil in late summer may be of some benefit in discouraging egg lay.

Are insecticides effective?
Grasshoppers are susceptible to many insecticides. However, insecticides typically do not persist more than a few days and grasshoppers may soon re-invade the treated area. The length of control will depend on the residual activity of the insecticides and the frequency of retreatment. Controlling grasshoppers over a large area will reduce the numbers present which can re-infest a treated area. Dimilin 2L provides long residual of young hoppers but is not effective against adults.

When should insecticides be applied?
Monitor grasshopper infestations and treat threatening infestations while grasshopper are still small and before they move into crops and landscapes. Immature grasshoppers (without wings) are more susceptible to insecticides than adults.

What about insecticide baits for grasshopper control?
Sevin 5 Bait is a ready-to-use bait which can be applied to many crop and non-crop sites, including around ornamentals and many fruit and vegetable crops. For those wanting to make their own grashopper bait, the labels for Sevin XLR and Sevin 4-Oil ULV provide directions for mixing these products with cereal grains to make a 2% to 10% carbaryl bait. The bait is labeled for use in rangeland, wasteland, ditch banks and roadsides. The label further states the bait is for use “only by government personnel or persons under their direct supervision (e.g. USDA, state and local extension personnel, etc.)”

Are biological control products such as Nolo Bait, Grashopper Attack, and others effective?
These products contain spores of a protozoan called Nosema locustae, formulated in a bait. Grasshoppers consuming the bait become infected by the Nosema organism. Some immature grasshoppers die while adults often survive but females lay fewer eggs. Nosema baits act too slowly and kill too few grasshoppers to be much value when the need for control is immediate.

Some insecticides for controlling grasshoppers in the home landscape at present (2003) include:

  • Cyfluthrin. The active ingredient in Bayer Advanced Home and Garden Spray
  • Bifenthrin. Active ingredient in Ortho Ready-to-Use Houseplant and Garden Insect Killer
  • Permethrin. Active ingredient in Spectracide and other products.
  • Acephate. Active ingredient in Orthene (at present, but being phased out).

Note: Tempo (cyfluthrin) and Demon (cypermethrin) are labeled for use by Professional Pest Control Operators (2003) for insect control in lawns and landscapes.

What insecticides can be used in ornamental production?
Several products may be used including those containing bifenthrin, lambda-cyhalothrin, diazinon, dimethoate, malathion, acephate and carbaryl (2003).

For more information, see: Extension bulletin L-5201, Grasshoppers and Their Control.

aggie-horticulture.tamu.edu

HOW MANY EGGS DOES A GRASSHOPPER LAY?

Grasshoppers live in most parts of the world, except in the cold regions near the North and South poles. Female grasshoppers lay as few as two or as many as 120 eggs at a time. The eggs are held together by a sticky substance made by the female’s body and are packed into the holes dug by her ovipositor, a sharp part of the rear of her abdomen.

After the eggs are put into a hole, the female sprays more of the sticky material over them. The material hardens quickly into a waterproof covering. The mass of eggs is called a pod. The number of pods a female lays varies among individuals and species.

Most kinds of. grasshoppers begin to lay their eggs in late summer and continue into autumn. The eggs hatch the following spring.

Unlike the young of most other kinds of insects, newborn grasshoppers look like the adults except that they have no wings. During the first 40 to 60 days after birth, the young grasshopper molts or sheds its shell and grows a new one five or six times. The wings grow to full size during the last molt, when the insects reach adulthood.

Grasshoppers live in fields and meadows where they eat plenty of leaves. Some kinds of grasshoppers eat only certain kinds of plants while others eat any plant they can fnd. They destroy whole crops of alfalfa, clover, cotton and corn and other grains.

There are two main groups of grasshoppers: long horned and short horned. The animals are divided according to the length of their antennae or feelers, which are also called horns. Short horned grasshoppers are usually called locusts.

A grasshopper has two pairs of wings. The front wings are narrow and tough and they cover and protect the large, thin hind wings. When the insect rests, its hind wings fold up like fans under its front wings. When a grasshopper flies, the downstroke of the wings gives the insect “lift” and moves it downward. The upstroke helps keep the insect moving until the wings reach the down stroke position.

A grasshopper has six legs and uses all of them when it walks. The front legs hold food when the animal eats. The hind legs are much longer and stronger than the others and have powerful thigh muscles. These muscles supply the force that pushes the insect forward in a leap, or shoots it into the air to fly.

The grasshopper is an insect that can leap about 20 times as far as the length of its body. If a man had that ability, he could leap about 40 yards.

When grasshoppers are handled, they “spit” a brown liquid that many children call “tobacco juice.” Some scientists believe this liquid may help protect grasshoppers from attacks by ants and other insects.

The abdomen of a grasshopper expands and contracts to pump air in and out of 10 pairs of breathing holes. These holes, called spiracles, are along the sides of the abdomen and thorax. Tubes branch out of the spiracles and carry air to all parts of the body.

www.youaskandy.com

Where grasshopper lay eggs questions

  • oversized back legs used for jumping
  • large compound eyes
  • fairly large size
  • it’s fluttery way of flying short distances
  • often grasshoppers make pops or snaps when they fly

THE GRASSHOPPER LIFE CYCLE

When a female grasshopper is ready to lay her eggs, there’s hardly anyplace better for her to go than an open, sunny field. She needs soil to be loose enough for her to work her rear end into it. Once her rear end is well underground, while she is laying her eggs, a frothy, gluelike substance is deposited over them. This substance hardens around the eggs as it dries. The frothy mass, which can be called an egg pod, dries into something like a stiff sponge, so that when the eggs hatch there’ll be plenty of air for the newborn, and it won’t be too hard for the newborn to escape. The number of eggs in a pod varies from individual to individual, and species to species — maybe as few as six or so, or more than 150. Each female deposits several pods. Some species, instead of laying in pods, just cram them haphazardly here and there in the ground.

So, when young grasshoppers emerge from their eggs, they find themselves inside a honeycombed egg pod, and buried underground. They must push their delicate bodies upward through the soil, especially using their long back legs. During this process their bodies are covered by a membranous hatching skin, which to some degree both protects the body’s delicate parts, but also restricts movements of the legs, making it even harder to push upward.

At the ground’s surface, the hatching skin comes off, giving the legs full mobility. Grasshoppers undergo simple metamorphosis, so immature grasshoppers look more or less like adults, only smaller. As nymphs grow, they molt several times, shedding their “skins,” or exoskeletons. As with other insects that undergo simple metamorphosis, each progressive stage of nymph development is referred to as an “instar,” so we might speak of a 2nd instar grasshopper or a 4th instar one. The final molting results in a full-size adult with wings. Though it varies with species, five or six instar stages usually take place. The time from egg to adult typically is 40 to 60 days. That’s probably a 5th instar nymph in the picture below:

The above grasshopper is clearly a nymph because its wings are so short. The wing is the oval, finely pitted item appearing to issue from beneath the cape-like “back shield,” or prothorax. On an adult grasshopper the wings would project well beyond the abdomen’s rear end, but you can see that on this nymph it reaches only about a fourth of the distance.

GRASSHOPPER CLASSIFICATION

Grasshoppers belong to the insect order Orthoptera, which also holds katydids, crickets, mantids, walkingsticks and cockroaches.

But, thing is, when you look at all the kinds of grasshoppers in the world along with all known grasshopper relatives, it becomes hard to decide where grasshoppers end and other insects, such as crickets and katydids, begin and end. According to the Peterson Field Guide A Field Guide to the Insects, here is one breakdown of the different kinds of grasshoppers found in North America:

GRASSHOPPER GROUPS
found in North America

  • Short-horned Grasshoppers, family Acrididae
  • Long-horned Grasshoppers, family Tettigoniidae
    • Cone-headed Grasshoppers, subfamily Copiphorinae
    • Meadow Grasshoppers, subfamily Conocephalinae
    • Shield-backed Grasshoppers, subfamily Decticinae
  • Pygmy Grasshoppers, family Tetrigidae
  • Monkey Grasshoppers, family Tanaoceridae
  • Eumastacid Grasshopper, family Eumastacidae

Other field guides group them a little differently, plus some experts would refer to our “Meadow Grasshoppers” as “Meadow Katydids,” and make other similar name changes. The truth is that there’s no point to debate what’s a grasshopper and what’s not. The word “grasshopper” is standard English, but it has very little if any scientific value.

If you’d like to see the current breakdown of families and subfamilies in the Orthoptera, showing how grasshoppers mix in with crickets, katydids and the rest, check on the NCBI Taxonomy Browser’s Orthoptera Page.

You’ve probably heard of plagues of locusts and how sometimes vast clouds of them darken the sky. Locusts are grasshoppers. You may be interested in Naturalist Jim’s experience with locusts in Mexico, and seeing some pictures, as reported in his Naturalist Newsletter.

www.backyardnature.net

Where grasshopper lay eggs questions

The name Grasshopper describes a number of insects that fall under the scientific “suborder” Caelifera, which is in the order Orthoptera. Within this suborder there are over 11,000 species of grasshopper. That’s a lot of types of grasshoppers!

Like all insects the grasshopper has six legs, a head, thorax, and abdomen. It also has an exoskeleton which is a hard outer surface that protects its softer insides. They have two pairs of wings. The back wings are larger while the front wings are small and fairly hard. Their back legs are large helping them to jump.

They are normally brown in color, but they can vary in color including yellowish brown, reddish brown, and light green. Some are even striped.

These insects live all around the world except where it is too cold like the north and south poles. They have adapted to most every habitat including deserts, forests, and grasslands.

What do they eat?

Grasshoppers eat plants, primarily leaves, grasses, and cereal crops. A lot of grasshoppers can eat a lot of food and can cause serious problems for farmers by eating all of their crops.

How do Grasshoppers make noise?

Male grasshoppers will make a singing sound by rubbing a hind leg against one of their hard forewings. The rough leg causes the wing to vibrate and make a sound, almost like a bow playing a violin.

How are they different from Crickets?

Grasshoppers and Crickets are similar insects, both being of the order Orthoptera, but they are different and actually are in different scientific suborders. The main differences may be hard to see:

  • Grasshoppers have shorter antennae than crickets.
  • Grasshoppers make sounds by rubbing their forelegs against their wings, while crickets rub their wings together.
  • Grasshoppers hear with their abdomen, while crickets listen with their legs.
  • Grasshoppers are diurnal (active during the day). Crickets are nocturnal (active during the night).
  • Grasshoppers only eat plants, while crickets will eat other animals and are omnivorous.

What are locusts?

Locusts are a type of grasshopper. They typically live alone, but are famous for forming giant swarms that can swoop down and destroy massive areas of crops.

Fun Facts about Grasshoppers

  • A lot of people around the world eat grasshoppers. They are a good source of protein.
  • They lay eggs that hatch into nymphs. As the nymphs grow into full size adults they will molt many times.
  • The villains in the movie A Bug’s Life by Pixar are grasshoppers.
  • They have many predators including birds, sp >

www.ducksters.com

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