Many bluebirders swear that supplying mealworms has really made a
positive difference during times of stress.- when spring suddenly turns
back to winter, when constant rain and/or cold cut off insect supply for
the young. And many of us also find satisfaction and pleasure in
supplying wintering chickadees, nuthatches, and other songbirds as well.
Feeders can range from empty tuna cans swinging from a roof overhang
to fancy feeders of wood and glass, similar to seed feeders, but with
holes in both wooden ends. These are now being shown in mail order
catalogs. Ahlgren Construction (address on mail-order pages) has the
simple ones, and the cedar/glass feeders available at $15plus
$5shipping. Carrol Henderson's Woodworking for Wildlife (see also mail
order) has plans for a seed feeder which is virtually the same, without
the 11/2" round or Peterson oval hole in either end.
The plan below, taken from the article by Nola Aiken in the Jan/ Feb
'99 Bird Watcher's Digest (p. 86), is easy to follow. Instead of placing
mealworrns in ceramic dishes within the feeder, her late husband used
pieces of panel molding shaped like a J tacked 2" above the floor
on the wooden ends. Worms could crawl all over the floor, but not out if
ends of the j-molding were tight against the sides of the glass. Nola
graciously gave permission to reprint the plans.
Note: Initially, you may want to leave one glass side off, and/or put
strips of masking tape horizontally across the glass, if bluebirds seem
to be bothered by it, or have just one side glass or plexiglass, the
Chickadees don't seem to mind freshly frozen mealworms, but other
birds might. Dave Ahlgren suggests: if you feed mealworms to wintering
songbirds and worry that they won't eat worms that freeze, securely set
the dish of meal worms in the heated birdbath! Bob Anderson, Olmsted
Co., devised a heat tape wrap around the tuna can holding the mealworms.
Others have devised a low-wattage light bulb underneath a cutout in the
floor. An adaptation of the heated bird bath (October 1998 Bluebird
News) could be used.
By John Thompson
Mealworms are an excellent supplement to bird feeding as they provide
additional protein to bluebirds' regular diet of 85% insects and 15%
seeds. When those early spring bluebirds arrive and insects are not
abundant, the availability of mealworms in the vicinity of your bluebird
nestboxes may be the difference between attracting bluebirds back to
your yard or having them move to a different area to begin their nesting
Mealworms are easy to raise. Only a few basics need be followed to
start and maintain a mealworm colony for a constant supply. In addition
to bluebirds, mealworms will attract a wide variety of popular bird
feeder visitors. The Midwest birds listed below LOVE mealworms and may
even have a preference for them over and above black sunflower seed. In
other geographical areas an even greater variety of birds will be
attracted to mealworms.
For your own mealworm colony: order regular or fishing bait size
worms in bulk from a supplier. I get mine from Rainbow Mealworms P.O.
Box 4907,126 E. Spruce St., Compton, CA 90220. To order by phone:
1-800-7779676. 2000 mealworms will cost $9.75 plus shipping. (Smaller
amounts are available.) Rainbow guarantees quality condition on receipt.
Never order Giant or Jumbo size- they do not keep or reproduce well.
A 5-gallon plastic pail works well. Buy enough oat bran to fill half
the pail. Oat bran is usually available in large food stores, food
co-ops or feed stores. A year's supply will be only a few dollars. When
received your mealworms will be packed in crumbled newspaper. Shake them
out into the pail. Put no more than 1,000 in one pail. Overcrowding will
generate heat and will kill them. Keep out of direct sunlight. Avoid
freezing. Best temperature is between 45' and 75' F. They will thrive in
the coolest part of your basement. About every two weeks put, on a piece
of cardboard, a couple of lettuce leaves, a slice of potato or apple.
Never add additional moisture. As the mealworms consume the bran, a fine
dusty residue will settle to the bottom. The uneaten top portion of the
bran should be salvaged, along with the microscopic eggs of the beetle
stage, and the bottom portion discarded, about three times a year. Then
half fill the pail with new oat bran.
The mealworms, or larval stage you receive, will go through 10-20
molts, then into a white pupa stage and into the adult beetle. The
beetle is flightless, but you may wish to screen over the top of the
pail. Depending on food and temperature, the cyclic stages may be 100 to
several hundred days. Minute larvae will appear from the eggs and will
grow rapidly to size for bird feeding. When my colony mealworms grow to
a size comparable to those I received originally I remove them from the
bran pail, and put them in plastic containers to keep in the
refrigerator, where they will remain in the larval stage. You can freeze
some mealworms, which winter birds will eat. Freezing does not seem to
bother them; they are adapted to eating frozen food in winter. But DO
NOT supply frozen worms when adults are feeding young nestlings or
While special feeders are available, I use a small tin or plastic
container near where the bluebirds are active. One or 11/2 dozen
mealworms twice each day for each bluebird pair will keep them satisfied
yet not dependent on this supplement to their regular diet. You may want
to increase this when young birds are being fed in the nestbox.
Mealworms are a perfect lure for photography and close-up pictures.
Many excellent bluebird pictures attest to this. Nestboxes, mealworms,
bird baths, short grass, scattered perching sites, regular monitoring,
and predator protection will provide you with unlimited enjoyment of
" the bird that carries the sky on its back" (as well as many
other delightful songbirds).
Note: John Thompson has maintained a mealworm colony for ten
years. Others may have variations on raising mealworms. Experiment!
Whatever method works, mealworm feeding adds to the joy of bluebirding,
and can have a positive impact on nesting success.
Posted with permission from the February 1999 Bluebird Recovery
Program Newsletter "BLUEBIRD NEWS"