Illinois Natural History Survey Reports

              1
R e p o r t s
Summer 2007
No. 392
Developing a Regional
Monitoring Plan for
Chicago Wilderness
2
CTAP: 10 Years and
Going Strong!
3
Frequency of Early
Mortality Syndrome
in Southwestern Lake
Michigan Lake Trout
Populations
4
Species Spotlight:
Southern Flying Squirrel
6
The Naturalist's
Apprentice: Looking for
Signs
7
Continued on back page
INSIDE
Recent reports of the disappear-ance
of honey bees attributed to a
mysterious disease called “colony
collapse disorder” have brought
many issues to the public eye
concerning, among others, the
importance of beneficial insects,
the global movement of both
insects and their diseases, and the
impacts of species loss on human
activities and health. Not all
insects are pests, nor are all dis-eases
detrimental—many disease
organisms are used in control of
pests and all are part of the natu-ral
cycle of animals. But diseases
in insects we depend upon are not
always well understood and may
be devastating to agriculture and
the natural environment.
Honey bees are the most
easily manipulated of the world’s
pollinating species and, therefore,
the most intensively studied.
Even with an extensive knowl-edge
base concerning their patho-gen/
parasite complex, researchers
and producers still are faced with
unexpected epizootics and intro-ductions,
and the bee industry is
constantly focused on identifying,
treating, and avoiding various
natural enemies that threaten
its livelihood. For
example, in addition
to the recent colony
collapse disorder and
varroa mite infesta-tions,
a microsporid-ian
pathogen, Nosema
ceranae, previously
thought to occur only
in the Asian honey
bee, Apis cerana, has
now been found to
occur worldwide in
colonies of Apis mel-lifera,
the European
honey bee.
Like all other
animals and plants,
insects are victims of
many different types
of diseases-viruses,
bacteria, fungi, proto-zoa,
and nematodes.
Disease organisms of
any or all of these
groups are found
in any well-studied
host species. Like other natural
enemies, diseases are important in
maintaining insect populations at
levels that are actually optimal for
the species, preventing popula-tions
from outstripping their
own food supplies. In terms of
human interactions with insects,
we would be much worse off if
insects such as mosquitoes, black-flies,
house flies, and agricultural
pests did not succumb regularly
and in great numbers to diseases.
There are, however, insects such
as bees and silk worms, predatory
flies and beetles, and other man-aged
beneficial insects that benefit
humans, and there may be serious
consequences when they are dev-astated
by epizootic diseases.
The Insect Pathology program
at the Illinois Natural History
Survey partners with federal,
state, and university cooperators
to study diseases of both pest
and beneficial insects. Some of
the more recent research proj-ects
have dealt specifically with
beneficial species. One project
involves working with the USDA
Forest Service to identify and
mitigate the occurrence of disease
in several species of beneficial
beetles that are being used for
biological control of the hemlock
woolly adelgid. This Asian adel-gid
pest is devastating popula-tions
of eastern and Carolina
hemlocks in both horticultural
Diseases of Beneficial Insects
Bombus griseocollis foraging on purple cone-flower.
Photo by Lee Solter, INHS
The bee team (L–R):
Jamie Strange, Terry
Griswold, Sydney
Cameron, and Lee Solter.
Photo by Joyce Knoblett