Easy Monitoring Technology for the Schoolyard
Written by Judy Dulin
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Below, a student collects invertebrates by shaking leaf litter through a wire mesh into a pillow case. See more photos.
Photo by Charles Wilder. |
Sugar Baiting
- Sugaring for moths, one of the oldest collecting methods, involves the use of a specially prepared bait in which some form of
sugar is an essential component.
- The bait may be refined or brown sugar, molasses, or syrup.
- Such substances often are mixed with stale beer, fermented peaches, bananas, or some other fruit- there is no standard formula.
- Each lepidopterist has his/her own favorite recipe.
- One particularly satisfactory recipe uses fresh, ripe peaches; culls or windfalls are suitable.
- Remove the seeds but not the skins, mash the fruit, then place it in a 4-liter (1-gal) or larger container of plastic, glass, stainless steel, enamelware, or crockery with a snugly fitting but not tight cover.
- Avoid using metal containers that may rust or corrode.
- Fill each container only one-half to two-thirds full to allow space for expansion.
- Add about a cup of sugar and place in a moderately warm place for the mixture to ferment.
- The bubbling fermentation reaction should start in a day or so and may continue for 2 weeks or more, depending on the temperature.
- During this time, check the fermentation every day or every other day and add sugar until fermentation appears to have subsided completely.
- As the added sugar is converted to
alcohol, the growth of yeast slows and eventually ceases.
- After fermentation ceases, the bait should remain stable and should then be kept in tightly sealed containers to prevent
contamination and evaporation.
- If the mixture is allowed to run low in sugar during the fermentation process, vinegar will be produced instead of alcohol.
- It is therefore important to smell the bait periodically and to add plenty of sugar to avoid this.
- The amount of sugar consumed will be surprising usually over 0.4 kg per liter (3.3 lb. per gal).
- The bait should have a sweet, fruity, wine-like fragrance.
- A trace of vinegar is not objectionable but is better avoided.
- Canned fruit, such as applesauce, may also be used to make the bait, but inasmuch as such products are completely sterile, a small amount of yeast must be added to start fermentation.
- Although the bait may seem troublesome to prepare,
it keeps for years and is thus available at any time, even when fruit is not in season.
- Immediately before use, the bait may be mixed with 30 to 50 percent molasses or brown sugar or a mixture of these.
- This thickens
the bait so that it will not dry out so quickly, and it makes the supply last longer.
- This thickens
the bait so that it will not dry out so quickly, and it makes the supply last longer.
- The best time to set out the sugar bait is in the early evening before dark.
- It may be applied with a paintbrush in streaks on tree trunks, fence posts, or other surfaces.
- Choose a definite route, such as along a trail or along the edge of a field, so that later you can follow it in the dark with a lantern or flashlight.
- Experienced collectors learn to approach the patches of bait stealthily with a light in one hand and a killing jar in the other to catch the moths before they are frightened off.
- Some collectors prefer to wear a headlamp, leaving both hands free.
- Although some moths will fly away and be lost, a net usually is regarded as an unnecessary encumbrance, because moths can be directed rather easily into the jar.
- Sugaring is an especially useful way to collect noctuid moths, and the bait applied in the evening often will attract various diurnal insects on the following days.
- The peach bait previously described has been used in butterfly traps with spectacular results.
- However, collecting with baits is notoriously unpredictable, being extremely productive on one occasion and disappointing on another, under apparently identical conditions.
