Decomposition of a migratory hawk

In terms of avians being poached, hawks are often shot during migration in September. With the help of CSU graduate student Krystal Hans, and CMNH Ornithologist Dr. Andy Jones, we placed out a cooper's hawk (Accipiter cooperii) for decomposition. The photos below document the first couple of hours of activity.

13 Sept. 2007: This cooper's hawk was found dead and provided to the Museum. We will allow it to decompose for 4-6 weeks, study the insect faunal succession, and then provide the bones to the Museum's osteology collection.

13 Sept. 2007: Two hours post-exposure, green bottle flies swarmed the bird, laid eggs inside a wound on the ventral area of the carcass, and laid eggs underneath the carcass between the feathers and the ground.

13 Sept. 2007: Krystal collecting blow fly eggs (green bottle flies: Calliphoridae) from the cooper's hawk carcass.

FINAL COLLECTIONS

We have officially completed our collections from the bear and the pig. The animals were well-skeletonized, although the thick hide of the bear remained in large part. The bear still supported some invertebrates in some number (Omosita, Necrobia, misc. staphylinids, Stearibia nigriceps). Interestingly, the soldier fly Ptecticus sp. (recorded earlier in the summer) was also present in the adult stage. Its forensic importance is still unknown.

Our conclusions are that 1) a similar fauna attacks large mammals and humans alike, and 2) the decomposition of the bear may be slowed by a variety of factors including the thick hide and fat layer. Further, Lucilia illustris was the first arriver followed quickly by Phormia regina, which is expected. There were three distinct waves of maggot movement off the bear, one off the pig.



13 Sept. 2007: Graduate student Krystal Hans assists with invertebrate collections off the bear carcass.

13 Sept. 2007: The final stage of decomposition in the pig - dry remains.