INTO THE SECOND WEEK OF DECOMPOSITION
Decomposition has really progressed here during the early part of the second week the bear has been out! The maggots have grown, and huge numbers are reducing the mass of the bear. In general, we have seen a predictable sequence of insect species. However, a few surprises have come up! Here is what we found during 29 and 30 May 2007....
30 May 2007: The maggot mass has increased dramatically. There are 10's of thousands of maggots throughout the abdomen and thorax, as well as the orifices of the head. Adult fly activity is heavy. Beetles (Staphylinidae, Histeridae, Silphidae) are common.
30 May 2007: The head is still very active. Note to the left of the nose is a large (about 1 inch in length) carpenter bee - similar to a bumble bee. Up to 3 individuals have been observed around the nose and mouth sipping decompositional fluids. This is probably an excellent nitrogen source. These insects only became apparent at the carcass near the end of the first week of decomp.
30 May 2007: The maggot mass is huge! You can hear it when close up. These are mostly maggots in the third (final) instar, or stage of larval development. They are widespread throughout the carcass. Many have apparenetly embedded themselves into the surface of the skin and require a quick pull to free them from the carcass for collection. The stench present emits what I feel is almost an ammonia-like smell on top of the pungent odor of decay.
30 May 2007: An interesting aspect of maggot biology is the "post-feeding" stage. After getting a full gut, maggots move off a carcass (or corpse) to find a remote area to burrow into the soil where they form the pupa. This is a good life strategy as many larger scavengers such as coyotes and raccoons engulf maggots when chowing down on the soft tissues... The photo above shows several maggots outside the exclosure. Hundreds of maggots were found by lightly scraping the soil surface around the exclosure.
29 May 2007: Overall, the maggot numbers and size of individual maggots have increased. Adult fly activity is still heavy.
29 May 2007: The head is still a site for a lot of activity...
29 May 2007: Feeding by maggots have begun to expose the skeleton of the bear's hind leg.
30 May 2007: The head is still very active. Note to the left of the nose is a large (about 1 inch in length) carpenter bee - similar to a bumble bee. Up to 3 individuals have been observed around the nose and mouth sipping decompositional fluids. This is probably an excellent nitrogen source. These insects only became apparent at the carcass near the end of the first week of decomp. 30 May 2007: The maggot mass is huge! You can hear it when close up. These are mostly maggots in the third (final) instar, or stage of larval development. They are widespread throughout the carcass. Many have apparenetly embedded themselves into the surface of the skin and require a quick pull to free them from the carcass for collection. The stench present emits what I feel is almost an ammonia-like smell on top of the pungent odor of decay. 30 May 2007: An interesting aspect of maggot biology is the "post-feeding" stage. After getting a full gut, maggots move off a carcass (or corpse) to find a remote area to burrow into the soil where they form the pupa. This is a good life strategy as many larger scavengers such as coyotes and raccoons engulf maggots when chowing down on the soft tissues... The photo above shows several maggots outside the exclosure. Hundreds of maggots were found by lightly scraping the soil surface around the exclosure.
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