Jan,
My son tells me about the honey ants of South America that the workers run
around and gorge on honey (or other sweet nectars).  Then, during the winter
(?) they hang from the ceiling of the tunnel and allow the other ants to suck
the honey from their abdomens (he said it is like suckling--he is 8 1/2).
 Perhaps you could let your carpenter ants feed on honey soaked wood and then
they would taste sweet without the fat of chocolate. (Martha & junior trivia
expert)

P.S.  You'll see below that I stand corrected on my larva comment--apparently
"exoskeleton to be" is higher in clacium than the crunchy kind.

Patricia,
 I agree that dietary sources of calcium are preferable, however,  it is
difficult to get the amount of calcium recommended from vegetable sources.
Here are some calcium sources and amounts: Wonder calcium enriched bread (2
slices) 580 mg, Total cereal: 250 mg, tofu: 150 mg, sardines (2 oz, canned in
water, drained): 185 mg, Turnip greens (1/2cup cooked chopped):99, broccoli
(1/2 cup coooked, chopped) 36 mg.

And now, just to prove to all of you that I am not completely off my rocker
(Jan--maybe this would be good in the Globe--ha): My source is Am J. Clin
Nutr 1991;54:281S-7S "Calcium in evolutionary perspective."  Calcium from
insects and wild game (nutrients/100 grams--approx 3.5 oz):  Adults
(grasshopper, spider, preying mantis, moth): 116.9 mg  (163.8 calories too!),
Larvae (128.8 mg (328.4 calories), wild game:14.2 mg (133.1 cal).

Martha Grodrian Brower RD LD IBCLC
"Motto:  The Calcium Crumbles Here"