Data from rearings

17 June 2007: Not much new happening on the bear itself. Still some small flies and carrion beetles, but with some rain this morning we observed a few black blow flies (Phormia regina) exploring the surface of the carcass.

17 June 2007: On the other hand, our rearings of insects taken from the carcass or wandering from the carcass are yielding good data! The idea is simple. Maggots are relatively challenging to identify to species. We collect maggots, but simultaneously place living ones on raw beef in containers to raise the maggots to the puparial and then the adult stage. This helps narrow the possible range of taxa represented by the maggot collections.

Our techniques are nothing special. We take some damp paper towel and in it place a cube of beef approximately 1"x1"x1". This is wrapped loosely in some aluminum foil, and this packet is then placed on top of some vermiculite or saw dust. When the maggots mature, they will wander off the meat (just like they do on the carcass) and move the saw dust to form the puparium. We have to continually check the packet, as some maggots don't go far and form a puparium in the foil. These are just removed and placed in the saw dust.

If we have maggots moving off the carcass, we collect these too, and place them in separate containers with the date and time of collection. The maggots are put into a pile of saw dust and allowed to pupate. The photo above represents the results of collecting 75 wandering maggots collected about a week ago. All appear to be Phormia regina. I placed this container in the freezer today, and will leave overnight. They will then be taken to the lab for identification and recording of data. Some representative specimens will be mounted on pins, labelled, and placed in the forensic entomology collection of the Cleveland Museum of Natural History.