Sexing | Wing Length | Mass | Wing Condition |Wing Damage | Spore Load | Behavior | Vital Statistics

Spore Load:

In a long-term study of the incidence of a protozoan parasite (Ophryocystis elektroscirrha) that infects monarch butterflies, we have found very interesting patterns in the degree to which different monarch populations are infected (Parasite Study).

We assess whether monarchs are infected with this disease in a way that is relatively easy and inexpensive, and most importantly, does not harm the monarch. To do this, first touch a 1 cm x 1 cm square of CLEAR scotch tape to the butterfly’s abdomen, removing a small patch of scales. It is easiest to this holding the tape with a tweezers. Place the tape on either a clear glass slide (for viewing under a compound microscope) or a white index card (for viewing under a dissecting microscope). Be sure to write on the slide or the card which butterfly the scales came from. View the tape under 12 to 40 X magnification. If the butterfly is infected with this parasite, you will see small football-shaped spots among the much larger butterfly scales. These are spores of the parasite. Count (or approximate) the number of spores on the tape, and assign the butterfly a score:

0: no spores seen

1: 1 spore

2: 2-20 spores

3: 21-100 spores

4: 101-1000 spores

5: over 1000 spores

Very few (less than 5%) of butterflies in the eastern migratory population are infected with this parasite. More (about 60%) are infected in the western migratory population, and almost all of the monarchs in southern Florida are infected (except in the fall, when migratory butterflies join the population).

Behavior:

We record if the butterfly was flying in a straight line (and if so, in what direction), nectaring, laying eggs, mating, roosting in a tree with other butterflies, flying in a nondirectional manner, or chasing other butterflies just before we caught it. Collecting this information in different places and at different times can tell us a great deal about the yearly migratory cycle of monarchs.

adult monarch nectaring

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