Lepidoptera Breeding an Rearing: Introduction

Welcome to this section created to provide informations on Lepidoptera. TTB is dedicated to Lepidoptera breeding, focusing on Saturniidae and Sphingidae families. This section wants to provide a mixture of insect care informations and basic material related to insect biology. This section is still incomplete, many small articles are on-going!

Arguments will be categorized and discussed per topics. Initially, informations will be divided according to the animal stage (e.g. egg, larvae, pupae, adult for holometabolous insects Wiki on Holometabolism), since the breeding conditions change dramatically depending on it. Other articles will be dedicated to specific subjects as diapause, basic rules for ecological safety or species specific rearing protocols.

Insects show an incredible variation in forms and colors; actually they are the largest class in the animal kingdom in terms of number of species. For these reasons there is no unique way to breed! Every species has its own necessities since it has evolved in a different ecological context. 

Graph from Fossil Focus by Ben J. Slater. Estimates based on data presented by Purvis and Hector 2000

Insect are animals that apply the r-strategy (rate) in the struggle for survival (check Wiki r/K for more info on this subject). In poor words this means that they prefer to produce a numerous offspring without investing energy in their care; this is in contrast, for example, with mammalian strategy. In natural populations, fertilized females produce a large number of eggs, out of those eggs a very small percentage will reach adulthood. In artificial broods this trend is inverted and breeders, in optimal condition, are able to maximize the survival rate. Generally, an insect breeder will not be able to keep rearing all the offspring of his broods.

If we consider the success in breeding, a very important variable is the breeder’s setup, there is no way to completely standardize breeding conditions without a full-equipped laboratory. Even if a breeder follows very precise rules, he won’t be able to control every variable at his place. Causes of unexpected problems, in those contexts, are very difficult to precisely determine. The quality of the air changes from place to place as many parameters that influence the health of the broods. More delicate species will suffer more compared to others. But do not worry, with some tips and a little bit of experience it will reveal easy to breed them.

By the way…Back To Breeding infos… 

1) When to breed?

Always! Although breeding in winter could be harder and many host plants are not available in this season (deciduous plants), it is possible to keep on rearing insects all year round.

2) Where to breed?

The setup to rear insects generally consists in the inside or the outside of the breeder’s private home. Outdoor rearing is possible and is recommended with species that are very sensitive to ventilation or species that are naturally present in breeder’s area. This approach depends on the geographic area in which the breeder lives. In some cases, or seasons, the indoor breeding could be the only option. The setup will be described in details in the corresponding sections, according to the stage of the animal. Insects can complete their life-cycle (that is the actual purpose of every breeder) in a relative small amount of space. For example, a stock composed of 20 Samia ricini (Lepidoptera, Saturniidae) can be grown to full size in a 30x50cm cage (TTB will always refer to scales using the international metric system), although more than one cage is recommended for adult care. 

3) Environmental variables

This topic will be further discussed in other sections, this is a quick overview.

When approaching a new species, the initial data which is available is the origin. The origin tells a lot on how to optimize the conditions, according to the original habitat. Invisible things are also part of the habitat and can’t be controlled (Bacteria for example), for this reason the outcome of reproducing the original habitat can be negative. The optimal condition is the setup that works in the place where is settled, independently of what is reported in other context.

– Temperature(T) is a key variable. For the species that we generally offer, standard room temperature (RT) is sufficient to achieve good results. For RT, here we refer to the normal temperature present in warmed houses, with no additional warming for the insects (generally between 18°C and 22°C). Specifically warm up Lepidoptera species is possible, but could present side-effects as drying the environment. Temperature shifts can induce metabolic changes in insects, as stimulating the onset or the end of diapause. It is very important to know how is the natural life-cycle of the species we breed. Always check where the species came from and how is the temperature there. In order to understand how to deal with origin (internet provides all the data easily), go to the Useful websites sections for more valuable links and informations.

-Humidity: here it will refer to “Relative Humidity(RH)” expressed as a percentage. As for temperature, the normal indoor conditions are accepted by many species. Winter is generally the driest season, in particular indoor because of warming. It is possible to spray caterpillars with water or to place wet paper inside the breeding boxes to increase humidity. Sadly, this could lead to side effects as the proliferation of many pathogens. For this reason is better to provide to the animals dry fresh leaves to eat and spray them sometimes, to increase humidity. According to our experience not spying the caterpillars at all results in a good percentage of success (with Attacus sp., Acherontia sp., Antheraea sp. and many more).

4) Clean environment and aeration

Maintaining the envirnoment clean is basic rule for Lepidoptera breeding. Butterflies and moths can be considered very sensitive to a dirty environment. By replacing the food and eliminating the stools often, sometimes more than once per day, it should be clean enough. To provide a well ventilated environment is very simple; plastic boxes can be modified using fine net mesh to cover them, ensuring the proper aeration. In most cases, it is possible to leave the box opened, caterpillars will stay on the host plant until there is enough food for them. Although some people report that is possible to breed caterpillars in closed plastic boxes, opening them only once per day, in our experience this leads to dramatic losses. 

Very important: insects breeding, Lepidoptera in particular, is not a big deal in terms of money and space; but pay attention to the time you are willing to dedicate them! Few time is needed but in a regular fashion. They suffer stress and starvation much more than other animals, thus be sure to have a constant eye on them, in order to ensure that things are going properly. This is fun!
Good Luck!