Last year at about this time we were wondering what a cold winter would
do to some of the common insect pests--unfortunately, it didn't do
much! Now, some may be wondering what a warm winter will mean to insect
populations. Climate usually has some impact on insect populations; it
may not be a great impact, but there may be something noticable in some
insects and other animals. In general, insects are more dependent on
temperature (an average daily temperature) than availability of food.
Long periods of warmer-than-usual weather in the winter may provide
some species the chance to survive the winter in larger numbers, and
perhaps get a jump-start on spring.
Many insects hibernate (in a sense) during the winter, while others
simply become inactive because it is cold. Mild to warm weather may
initiate breeding of insects such as mosquitoes, cluster flies,
boxelder bugs, and others. Hopefully, the natural parasites and
predators of these insects will become active at the same time. Warm
weather may give some insects the opportunity to have more generations
this year than usual; more generation may mean more of these critters
available during summer.
Some groups that may benefit from a mild winter include:
Slugs - These creatures are often pests in flower and vegetable gardens
in the spring--and there are few good measures to control them! (I
don't like wasting good beer!). Most slugs and other snails overwinter
in the egg stage and become active in early spring. A mild winter may
get some of them started early, and feeding on plants that are also
getting a boost by the warm and wet weather. Slug control may be a big
challange in the spring of 2008!
Spiders. These are predators and they depend primarily on insects for
their prey. Most spiders overwinter in the egg stage, but some as
spiderlings. An increase in the activity and availability of flies,
beetles, and other insects can provide for a large population of
spiders if the spiderlings can find more food in early spring (oh,
joy!). Daddy long-legs (not really spiders, but close enough) may get a
good boost from a mild winter.
Mosquitoes. These flies usually overwinter as adults, and they are
ready to go in the spring! They lay their eggs in standing water that
results from melting snow and spring rains. The larvae complete their
development in the water and adult mosquitoes are produced in a few
short weeks. The warm and wet weather could provide some added problems
in a few months. Homemakers should consider some early efforts to
remove standing water around the house. The best control is to prevent
the female from finding a place (standing water) to lay eggs, which the
larvae need for survival.
Fleas. What, you are saying! Not fleas! Well, fleas are a problem in
summer and fall primarily because of the relative humidity outdoors and
indoors. Humid conditions outdoors (summer) usually leads to increased
relative humidity indoors, and this may provide conditions suitable for
flea populations to increase. If we have a humid and warm winter, fleas
could become a problem, or at least get an early start in the spring!
Effective flea control in the winter can be acheived with regular
vacuuming of the pet's sleeping area. This will remove flea eggs and
the dried blood (from feeding adult fleas) that can accumulate in the
bed.
Carpenter and Small "Sugar" Ants. The colonies that are located within
structures (houses, barns, garages, etc.) are inactive during the
winter (due to a shortage of food), but often begin foraging in early
spring (February)--and are seen indoors. Outdoor colonies that live in
logs and trees are inactivated by the temperature (and a scarcity of
food), and forage in April. Colonies may become active earlier in the
spring if the winter temperatures are mild. If the winter continues in
a mild state, be prepared for an increase in these and other
ants--especially small "Sugar" ants. These ants are very responsive to
warm spring temperatures.
Termites. These wood-infesting insects are also very responsive to
winter and spring temperatures. Swarming is usually in April and May,
but it is very much linked to warm and wet weather. Certainly, warm
weather in mid winter will not result in swarming (at least outdoors,
but maybe indoors), but a continued mild winter could result in early
swarm dates in some areas that traditionally have mild winters
(tidewater region).
Gnats. These flies are perhaps the most common indicators of mild
winter weather. On warm, sunny days with little wind, these flies can
be seen in small swarms over the ground. They usually find some
"marker"--a light colored or dark colored area that is distinct from
the background, and over this area they will swarm for an hour or less.
Warm spells in the winter will provide these flies more opportunity to
swarm, more swarming means more mating, more mating means more eggs,
and then more gnats! Ain't life grand!
Warm Winters