People are often quite surprised when they see photos of so many eggs on one leaf. WHY? HOW? Let’s take a look at how and why we raise Monarch butterflies at Shady Oak Butterfly Farm.

At the farm, we begin with OE free ‘breeder’ butterflies. What are breeder butterflies? They are butterflies that are designated to pair and lay eggs. They are the parents of future butterflies at the farm. We are careful to keep a good genetic base, adding new disease free Monarchs to the breeder line of butterflies several times a year.

Other than new genes for our breeding stock, our Monarch eggs and caterpillars are not taken from the wild.

Eggs are removed from the leaves and disinfected with a bleach solution. These two YouTube links show how we remove eggs and disinfect eggs. Because the eggs were laid by dozens of Monarch butterflies, they aren’t clean. Many butterflies have touched them. The first meal of a Monarch caterpillar is its eggshell. We make that meal clean as can be.

Eggs are air-dried and placed in cups to hatch. A fresh tender leaf is added to each cup. As each caterpillar hatches, it crawls to the fresh tender leaf and begins eating. Each day fresh food is added to the cup until it is time for them to be moved to a larger rearing container.

The leaf with fresh little caterpillars is moved to a ‘tote’, lined with plastic (easy to clean), and with ventilation provided by adding screen to the lid. Gloves are worn and washed/changed often to keep things as clean as possible.

All of this is done in the safety of a laboratory. In nature, 98% die before they become adult butterflies. In the lab, we nearly turn that number upside down. The lab is designed to protect caterpillars from disease, predators, and parasitoids. We have three labs for caterpillars.

As caterpillars grow, they are fed milkweed that is grown in closed greenhouses. Wild butterflies (of any species) are not allowed in any of the six greenhouses at the farm. Wild butterflies often carry disease pathogens.

Caterpillars are fed every day, including Sundays and Holidays. Our Christmas and Easter begin with someone at the farm, feeding caterpillars.

Every rearing container is marked with the date the eggs were disinfected, the line of breeding stock, and any other important information. If a spider is found in the container, that fact is marked on the container. If we find a dead caterpillar, we know a spider probably killed it. We are cautious. Because we ship caterpillars, chrysalises, and adults, we cannot take chances like we could if we were enthusiasts taking caterpillars from the wild. When a caterpillar is taken from the wild, diseases and parasitoids are often already at work in the caterpillar. At our farm, disease and parasitoids are not tolerated. If two caterpillars die in a rearing container, the remaining caterpillars are euthanized unless we know that the deaths were from a non-disease or non-genetic origin.

At about two weeks of age, caterpillars being to attach to the lids of their rearing containers, dropping into a J as they prepare to pupate. The next day, each J’ing caterpillar pupates into a beautiful green chrysalis.

Three days each week, chrysalises are removed from their rearing containers. They are not allowed to emerge in the lab. One by one, they are carefully removed and placed in trays.

Chrysalises are taken to a lab that isn’t joined to the caterpillar lab.

In the chrysalis lab, they are sorted. The best are our breeders. They are taken to a different lab to be disinfected and placed in a mesh popup habitat to emerge. They are then checked for OE. Although we do not have OE at the farm, we add new breeder butterflies (genes) several times per year. We know that if a caterpillar eats an OE spore shortly before it pupates, the adult may have very light OE, so light that OE checks won’t show spores. As an automatic safety step, every breeder Monarch and Queen butterfly is checked for OE. We have a zero OE tolerance at our farm. If a butterfly has OE, it is to be euthanized. (For enthusiasts who bring in caterpillars and plants from the wild, OE specialists suggest different rules.)

Once they are checked for OE, they are taken to the “apartments”. This is the butterfly’s home. It lives its life in this screened ‘garden’, eating, mating, and laying eggs. Inside are nectar plants, fruit, and juice. One to two milkweed plants are added, according to how many Monarch butterflies are in the room. Fruit and juice are removed and replaced with fresh fruit and juice regularly. We provide everything they need without allowing in predators or disease.

The ‘apartments’ are inside a selected screened greenhouse. Plants are not in this greenhouse, except as we add them for nectar and egg production. This means that wild butterflies do not land on the outside of the apartments, dropping OE spores on the same screen that contains our breeder Monarchs.

They are allowed to mate as they wish, as often as they wish, to provide an even greater genetic base. Females continually lay eggs on milkweed plants in their apartments. The plants with eggs are taken out and replaced three times per week. Fresh milkweed plants are added to the apartments. Because the plants are cut back to an inch or two tall when we remove the eggs, these plants are returned to the greenhouse to grow more leaves. The base of the plant is covered to prevent eggs from being laid in that area. Eggs and caterpillars are not allowed in our greenhouses. Milkweed plants are totally separate from butterflies in any stage.

In the chrysalis lab,chrysalises are sorted according to species and possible physical damage. Any that are damaged are emerged together, separate from undamaged chrysalises. Because of this, we know that if a butterfly doesn’t emerge in the other emerging popups, it isn’t because the chrysalis was physically damaged. In this way, we know the percentage that do not emerge properly (if there are any that have trouble emerging). If several do not emerge, we investigate to determine the problem.

We raise over 30 species of butterflies and several species of moths, shipping to 40 exhibits throughout the United States, from coast to coast, north to south. Most exhibits prefer chrysalises, not adult butterflies. Because they are shipped, we must know that they will not emerge in transit. Chrysalises that are to be shipped the following week are placed in a 54 degree wine cooler to mimic nature’s fall temperatures. In cooler weather, butterflies take longer to emerge. Because of the wine cooler temperature, they can be shipped to exhibits the following week without fear of them emerging in transit.

Chrysalises of butterflies that are to be shipped as adults are placed in mesh popup habitats to emerge. Some species are glued to paper towels and hung. Others are laid flat on paper towels on the bottom of the habitat. (If you emerge Monarch butterflies this way, remember that plastic MUST be up or down, not to the side.)

Once butterflies emerge and dry their wings, they are ready to be shipped to exhibits, research facilities, USDA facilities, or other destinations.

Once caterpillars are fed, the laboratories are cleaned. Counter tops are wiped down with a bleach solution. Floors are mopped with a bleach solution. Sanitary rearing conditions are of primary importance.

After chrysalises are removed, the containers and lids are disinfected. A sink is set up in an outdoor room (good ventilation) for that purpose.

Totes and lids as well as mesh popup habitats are placed in a separate attached room to dry. The following day, they are ready for use.

While all this is going on, Matt is continually growing plants. The entire operation is based on healthy host plants for caterpillars. The greenhouses range from the 35 to 130 degrees throughout the year.

Charlotte manages the farm from the office. She oversees all aspects of the operation. Jennifer and Rachel feed caterpillars as well as take care of other parts of the farm. Rachel packs most of the orders. Michelle works in the office, helping with orders and keeping computers running properly as well as tending to freshly emerged adult butterflies. The farm is dependent upon these hard working individuals who are willing to put caterpillars before their own meals and comfort.