||May/June 2002 issue||
Friend or foe? |
It’s a bug’s life |
Grasshopper facts |
Grasshoppers on film |
Nature’s symphony |
Literary hoppers |
Fascinating grasshopper facts
Did you know?
1. Grasshoppers can sometimes benefit farmers. Turnbull’s grasshopper (Aeoloplides
turnbulli), a species found on the Prairies, feeds on plants we consider weeds. It
eats goldenrod, Russian thistle, kochia, lambsquarters and other well-known weeds. Another
species, the two-striped grasshopper (Melanoplus bivittatus), eats plants that
are toxic to cattle.
Flies are some of the most important enemies of grasshoppers. In this photo, a robber fly
has captured a white whiskers grasshopper (Ageneotettix deorum). Grasshoppers are
also attacked and killed by maggots of parasitic flies.
3. Grasshoppers are also eaten by birds, coyotes, skunks, reptiles, rodents, mantids, beetles
4. In some cases, a tropical fungus that does not harm birds might replace chemical insecticides
to control grasshoppers. Young pheasant chicks that consumed fungus-infected grasshoppers
stayed healthy, and showed no evidence of harm to their tissues or organs.
5. The "eardrums" of short-horned grasshoppers are clear, circular membranes (tympana)
located on the abdomen, just behind where the hind legs attach to the body. The hearing organs
of long-horned grasshoppers and crickets are found on the forelegs.
mandibles of grasshoppers occur in pairs and are situated so that they chew from side to
side, and are so tough they are not damaged when the grasshopper is eaten by a burrowing
owl. For example, when an owl eats 50 grasshoppers, almost the only grasshopper remains found
in the pellet (which is coughed up by the owl after grinding and digesting the food) will
be a few legs, 100 mandibles, and some other smaller grasshopper mouthparts.
7. Some grasshoppers spit a brown, bitter liquid as a defensive behaviour when they are
handled. This liquid is often called "tobacco juice."
8. Although it depends on the species and environment, when grasshoppers reproduce, the
female typically uses her spade-like ovipositor at the end of her abdomen to dig a small
depression in the soil. The eggs are then laid in this hole. After a few weeks of warmth
in the soil, the larvae hatch.
9. Grasshoppers grow and mature through a process called metamorphosis. The egg hatches
into a worm-like larva which moults to become the first in a series of nymphs. Nymphs look
like miniature adults without wings and reproductive organs. They moult and pass through
five or six stages on their way to becoming adults.
10. When grasshoppers moult, they swallow air to build up pressure in their bodies to split
the old cuticle.
The moulted exoskeleton, like the skin shed by a snake, is a perfect replica of the grasshopper’s
body. It includes the antennae and eyes, and even the insides of its mouth and anus!
12. Locusts are particular species in the grasshopper family which differ by having two
phases, or forms of existence. They usually exist in the "solitary" phase, but
under certain environmental circumstances they switch to the "gregarious" form
and behaviour. It is in this latter condition that the insects swarm and can cause considerable
damage to crops and wild vegetation. However, of the thousands of known grasshopper species,
only a handful of them form swarms. None of these species is currently found in Canada. Recent
locust outbreaks have been prominent in China, Tajikistan, Uzbekistan, Australia and Africa.
13. Some grasshopper species sing, but different groups make noises in different ways. Grasshoppers
belong to the taxonomic family Acrididae, with a number of subfamilies. Members of the subfamily
Gomphocerinae (tooth-legged) make sounds using a row of pegs on the inner hind femur. The
Oedipodinae (band-winged) grasshoppers clatter their wings together while in flight to make
noise, while the Tettigoniidae (long-horned grasshoppers and katydids) rub their wings together.
The subfamily Melanoplinae (spur-throated) does not sing.
14. Grasshoppers’ jumping abilities make them some of nature’s best athletes.
If you could scale up the jump of a 5-centimetre-long grasshopper to a human, the human would
be able to make a standing long jump of about 40 metres!
15. The special jumping legs of grasshoppers have another purpose they sometimes
drop-kick their frass (insect dung). Sometimes the frass remains stuck to the grasshopper
after defecation, so it flicks its hindleg to get rid of it. This probably has adaptive value
as a hygenic behaviour.
Photos courtesy of Dan