Download Northern Green-striped Grasshopper

SPECIES ACCOUNT
NORTHERN GREEN-STRIPED
GRASSHOPPER
(Chortophaga viridifasciata)
Vineyard Overview: This is one of the most
common grasshoppers on the Vineyard, locally
abundant in dry, open areas. It is also an insect that
flourishes in human–altered habitats, including
yards, roadsides, and pastures. The odds are good
that this insect already occurs in or near your yard.
But it can be abundant in natural habitats as well,
such as along the fire lanes in Correllus State Forest.
Identification: The Northern Green-striped
Grasshopper is a member of the band-winged
grasshopper family, though in contrast to some of its
relatives, this species has nearly colorless wings with
no strong coloration on them. The wings are evident,
though, when a disturbed adult leaps into the air and
takes flight: producing a distinct rattling noise while
in use, the wings can propel this insect many yards
from its launching point.
The Northern Green-striped Grasshopper overwinters as an immature
nymph, like this one. These are sometimes active on warm winter days.
Photo: Matt Pelikan
A little more than an inch long, the Northern Greenstriped Grasshopper has a misleading common name.
It actually comes in two distinct color morphs: one is
all brown, and the other is mostly green but with
brown wing-covers. Neither morph looks
conspicuously striped! While it isn’t a totally
diagnostic feature, this grasshopper has an obvious,
keel-like ridge running down the center of its thorax,
and this characteristic is helpful for identification.
found in mid- to late summer. But the Northern
Green-striped Grasshopper overwinters as a nymph –
an immature form that resembles a very small adult
with undeveloped wings. Nymphs can sometimes be
found during the winter, on warm days in sunny,
sheltered spots, when they rouse themselves and
feed. How much the nymphs mature during the
winter depends on how mild the season is, and this in
turn determines when the first adults (with fully
developed wings) can be found. In exceptional years,
adults appear as early as late April. But in any case, if
you see a mature grasshopper on the Vineyard any
time before the middle of June, it is almost certainly
this species.
But perhaps the most useful clue for identifying this
grasshopper is seasonality. Most grasshoppers on the
Vineyard overwinter in egg form, hatching in the
spring and gradually maturing into adults that are
Ecological functions: The Northern Green-striped
Grasshopper appears to be a generalist in terms of
diet. So even when it is abundant, it probably has
relatively little impact on any single plant species. But
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like other plant-eating insects, this grasshopper
probably exerts some influence on the growth rate
and abundance of particular plants. And it certainly
plays a role, through its digestive process, in breaking
down plant tissue into basic compounds that are then
available for use by other plants. Such “nutrient
cycling” is an essential component of a healthy
ecosystem.
can accomplish this by leaving parts of your yard
unmowed or leaving spent plants in flower beds
through the winter. For example, two places where
we routinely find this species overwintering are a
patch of bearberry on the south side of a picket fence,
and in clumps of big bluestem grass along the southfacing side of a concrete house foundation.
This grasshopper is also an important prey species for
larger insects and for many species of birds. In
particular, maturing nymphs in the spring are
increasing their activity around the same time the
first migratory songbirds are arriving. If you notice a
grackle or robin rummaging through the leaf litter on
the edge of your yard, it is likely that grasshopper
nymphs are among the prey items the bird is taking.
Since relatively few insect species are active at that
point in the season, the role of this grasshopper in
sustaining early bird migrants may be significant.
Strategies:
1. Provide food and shelter. Like other grasshoppers,
this species seems to fare best in settings that offer a
fairly high diversity of plants. Such diversity increases
the odds that plants suitable for the grasshopper’s
diet are available, and young, rapidly growing
vegetation (which tends to be more nutritious and
easier to eat and digest) is more likely to be present
throughout the season in a diverse area.
Northern Green-striped Grasshoppers, because of
their unusual life cycle, may be more reliant on leaf
litter and dead vegetation in sheltered spots during
the winter. Such spots keep the overwintering
nymphs out of sight of potential predators, and also
help them warm up on mild winter days so that they
can eat and advance their development. Of course
structurally complex vegetation is also important to
give this species shelter during the summer: a closely
cut lawn or an area with only sparse vegetation
doesn’t offer effective hiding places for an insect the
size of an adult grasshopper.
For both of these reasons, then, the best way to
encourage this species is to provide unmanaged or
lightly managed vegetation in dry, open areas. You
This adult Northern Green-striped Grasshopper, a brown morph, shows
the distinctive “keel” along the top of the thorax – a good ID mark for this
highly variable species. Photo: Matt Pelikan