Mealworms vs Black Soldier Fly Larvae

Black soldier fly larvae are the bigger, plumper, chewier of the two dried insects, and mealworms are the lighter, longer, crisper ones that blow around the run. The choice is mostly about handfuls and habits.

Two dried insects

A mealworm is the larva of a darkling beetle, and a black soldier fly larva is exactly what the name says. Both are sold dried, in bags, as treats for chickens and for wild birds, and both look like what they are: small, ridged, curled segments, tan to brown in color.

The simplest way to compare them is to tip a spoonful of each into your palm. The mealworms are long and slim and weigh next to nothing. The larvae are shorter, thicker and heavier for their size, and a spoonful holds fewer pieces. That one difference, size, drives most of the rest.

Size, crunch and how chickens take them

For a fair comparison at home, weigh a level tablespoon of each on a kitchen scale and count the pieces. The mealworm spoon holds many pieces and weighs little. The larva spoon holds fewer pieces and weighs more. A bag weight on its own does not tell you how many handfuls are inside, and the count does.

Hens take either one at once. Throw a handful of mealworms and the flock converges, snaps them up and looks for more in a matter of seconds. The pieces are small enough to swallow whole, and they are light enough to blow off a patch of dry ground, scatter into the grass and go missing. Toss them on bare dirt or into a shallow dish and not onto a breezy lawn.

Larvae stay where they land. The fatter pieces take a bite or two more to get through, and a hen will often carry one off from the crowd.

The trade off is plain. Mealworms are light and quick, and a scoop is a lot of pieces. Larvae are bigger and chewier, and a scoop is fewer pieces that last a little longer in the beak. Neither one is a better treat than the other, only a different handful.

Handfuls are best thrown, not poured. A pour lands in one pile and the top hens guard it. A throw spreads the pieces over a patch so the whole flock finds some. Neither insect replaces the feed in the feeder; both are treats, and treats for backyard chickens covers how much a flock gets.

Reading the analysis on the bag

Under AAFCO's model rules, a guaranteed analysis lists minimum crude protein and crude fat and maximum crude fiber and moisture, in percent. That is the line to look at. Put the two bags next to each other and read their analysis lines in the same order, naming each as from its own label.

The minimums and maximums are guarantees, not measurements of the bag in your hand. A minimum is a floor the maker promises to stay above, and a maximum is a ceiling. The real contents may sit well inside both.

A bag may print more than those four lines, and a calcium line is one that shows up on some labels and not on others. Compare like with like. A figure printed on one bag and missing from the other is not a comparison; it is a gap on one label.

Also read the ingredient line. A bag of dried insects should name one ingredient, the insect. Anything else on the line has been added, and the supplier's listing on this store will tell you the same if the bag does not.

A last point about the label: percentages are printed as the maker gives them, so compare one label with another label and not with a figure copied from a website. Two bags that name their numbers the same way can be set side by side. A bag and a web page cannot.

Storage and pantry moths

Dried insects feel dry and smell faintly of nuts and straw, and an open bag left on a shelf is a target. Pantry moths find grain and seed products and also dried insects. Keep an opened bag in a sealed jar or a tin with a tight lid, and use up older bags first.

A bag that has been in the cupboard long enough to have webbing, clumps or a musty smell is finished. Read the best by date on the bag, and do not trust the date once the seal has been broken for months.

Sniff and Shift makes its freeze dried and air dried treats in small batches in Malvern for dogs and cats, and none of that line is meant for chickens. For a flock, the chicken treats collection is the place to start. Reptile keepers use the same insects, and dried insects for reptiles covers them from that side.

Common questions

Which is bigger, a mealworm or a black soldier fly larva?

In the dried form, mealworms are longer and slimmer, while the larvae are shorter and thicker. The larvae feel heavier for their size. Tip a spoonful of each into your palm to see it.

Do dried mealworms blow away in the wind?

They can, because each piece weighs very little. Toss them onto bare dirt or into a shallow dish. On a breezy lawn they scatter and get lost.

How do I store dried mealworms?

Keep an opened bag in a sealed jar or a tin with a tight lid. Pantry moths find dried insects and seed products. Throw out any bag with webbing or a musty smell.

What does a guaranteed analysis on an insect bag mean?

AAFCO describes it as the label's listing of minimum crude protein and crude fat and maximum crude fiber and moisture. Read each bag's lines in the same order. Do not compare a figure on one bag with a missing line on another.