April 2021 - 36

This rock wren is one of many animals in Wyoming that relies on insects as a food source. (Photo by Kathy Lichtendahl)

Sustenance

Because insects reside near the bottom of the food
chain, they serve as major sources of nourishment
for other insects along with fish, birds, reptiles and
mammals. Over the years, I have met many anglers
eager to recount the current state of affairs regarding
that year's stonefly hatch because they know it will
affect their sport.
Several species of birds have diets exclusively of
insects, and there are a surprising number of birds we
tend to think of as seed and nectar eaters that rely on
insects for necessary protein in their early days of life.
For example, hummingbirds often prey on insects to
feed their young. Sage grouse also rely on insects when
they are young.
" Insects are an important food source for sage grouse
chicks. Up to 75 percent of their diet may be composed
of insects. During the first four weeks of life especially,
chicks need a lot of protein to survive, grow and start
flying, " said Leslie Schreiber, sage grouse and sagebrush
biologist for the Game and Fish.
Insects may not be the first things that come to mind
when people consider the diets of mammals but, they
can be a significant source of food for wild felines and
canines as well as weasels and bats. Research and monitoring efforts in Wyoming over the last several decades
has documented the role of the army cutworm moth
as a source of calories for grizzly bears. As the human
population continues to expand, the importance of
insects as food for people, known as entomophagy,
grows as well. North America already lags behind much
of the world in its acceptance of insects as sustenance.
More than 80 percent of the nations on the planet
regularly eat bugs as part of their diet.
36 | April 2021

Predation

Insects also serve the function of predators for
other insects. Dragonflies, for example, are master
hunters, able to see and fly in any direction, even
backward. One adult dragonfly is capable of eating
hundreds of mosquitoes in a single day. Mosquitoes
are one of the low percentage of insects considered
pests and can spread disease to humans and animals.
We have learned to take advantage of predatory
insects by harnessing their hunger for specific plants
and other insects and putting it to work in the field
of biological control.
The need in this field has grown over time as
invasive species become more widespread around
the world. What makes invasive species dangerous
is they often have no natural enemies in their new
environment. That means they have free reign to
thrive, often at the expense of native vegetation and
insects. One solution is to import insects to control
the spread of the unwanted newcomer. Before taking
this action, scientists must be sure the imported
insect will only affect the targeted species and not
harm native plants and animals.
" Insects introduced for weed biological control
are very specific to the weed species they are meant
to control, " said Tim Collier, an entomologist at
the University of Wyoming. " The United States
Department of Agriculture rejects importation of
insects that pose risk to native species and crops. For
biological control of insect pests, the USDA also
regulates importation and rejects insect predators
and parasites that might harm native insects. The
former also go through screening to make sure they
do not attack native insects. "

April 2021

Table of Contents for the Digital Edition of April 2021