I began using this "Calling Cage with Electronic Aid for the Study and Enjoyment of Saturniidae" in the early 70's, when I started out in the security and fire protection business. I had already been a Sat enthusiast and breeder for many years. To facilitate one of my most favorite aspects of rearing, observing the arrival of male moths to calling females, I designed a simple wood and screen cage with a single circular opening on one side.

All one has to do with this is place the female Sat inside and she can then be easily transported to the desired location, where the cage is set down with the opening facing sideways. The cage provides good protection from predators, and, since new females are generally not very active, the risk of loss is minimal. The design is particularly handy when I want to quickly drop off a moth with a friend (usually with eager children) to study an unfamiliar area.

At first glance, it might seem as if this cage would present a formidable obstacle to arriving males. However, my experience has been that they have no difficulty finding their way to the opening, and then inside. The next day, it's a simple matter to pick up the cage, with mating pair, and bring home.

The picture (above) shows this device in place . Mounted to the cage, is the optical head. This consists of four GaAs infra-red emitters surrounding a phototransistor.

The emitters broadcast pulses of infra-red which are not visible to the moths. The pulse mode of operation allows driving the emitters at maximum power output, while conserving current overall, so it is practical to operate this device from a 12-volt lantern battery.

The emitters operate at a peak wavelength of 950 nm, which closely matches the spectral properties of the phototransistor. This, along with the pulse mode of operation, helps prevent the device from responding to ordinary background radiation . Detection, with this device, works similar to radar in that its back-scattered infra-red energy from the target, received by the phototransistor, triggers the output circuitry.

The box mounted beside the cage holds this circuitry which consists of :

1) Drivers for the emitters; duty cycle is 100 usec pulses, 100pps

2) An amplifier for the phototransistor signal

3) Processing logic; the device must receive three above threshold events in sixteen consecutive transmitted light pulses in order to activate the output circuit .

4) Output circuit to the remote sounder alarm (not shown) .

For a moth size object, this device has a range of about one-foot. Even with the pulse mode operation, and logic described above, it is not possible for even the speediest of fliers to get through the field of range undetected. This, I have found, is just about right to detect a moth early enough without causing a lot of false alarms from other sources. About half the time when I wake up and get to the cage, the male is already inside; the other half of the time, he (or they) are still circling the cage.

This device resulted from a work project, then-called "Infra-red Proximity Detector". I made some adaptations, and created an electronic device which monitors the opening of this cage, and sends a remote alarm when a male approaches. This has allowed me to know precisely when males arrive and observe the event, without camping out all night.

I have used the device successfully for many years with all major Sat groups except the Ceratocampinae, on which I hope to be trying it this next season, for the first time, with a number of C. regalis .

After the successful mating, I set the cage with opening facing down over a sheet of newspaper, and let the female deposit her eggs. After a day or so, when the egg chorion has hardened, I remove these from the cage surfaces with my fingernail, and roll the eggs out a small opening cut in the screening.