Bones of Extinct Flightless Duck Discovered In Central California
July 19, 2005
Contact: Christina S. Johnson, csjohnson@ucsd.edu, 858-822-5334
Leg bones from the flightless duck Chendytes. The top bone is a tibiotarsus, the bottom a tarsometarsus. [Photo: Terry Jones, Cal State San Luis Obispo]
Terry Jones, a Cal Poly San Luis Obispo social sciences professor, has made an unexpected find: the discovery of skeletal remains from an extinct flightless duck in the archeological remains of the some of the region's most ancient hunter gathers.
Jones is in the process of trying to have the rare bone fragments carbon dated. So far, this is proving difficult because of the absence of sufficient collagen on most of the bone pieces. Collagen is a more reliable source of carbon for dating than carbon from bone itself.
The archeological remains that Jones is analyzing were excavated during the construction of the nuclear power plant at Diablo Canyon in San Luis Obispo. These remains represent what archeologists call a "kitchen midden," - a refuse heap containing shell, bone and other remnants of human occupation. The Diablo Canyon site is believed to represent one of the longest, continuous records of the coastal human settlement in Central California. The oldest layer of refuse may date back 10,000 years.
Although dating the duck, which is in the genus Chendytes, accurately is a work in progress, the layers
Leg bones from the flightless duck Chendytes. The top bone is a tibiotarsus, the bottom a tarsometarsus. [Photo: Terry Jones, Cal State San Luis Obispo]
from which the bones were extracted suggest it was being hunted 10,000 years ago and that it went extinct no earlier than about 4,000 years ago. If this is true, it is has exciting implications for how ancient people hunted and why the bird went extinct.
These birds, the size of a turkey, could swim and dive, but they could not fly. They were extremely
vulnerable to predation by coyotes, foxes and bobcats. “They were literally sitting ducks,” Jones explained. “They could not have lived on the mainland because they would have been helpless against terrestrial predators. They had to be living and nesting on offshore rocks and islands.”
These areas could be reached only by boat, Jones said. In other words, the presence of Chendytes bones strongly suggests people were building and using boats much earlier than many archeologists have thought.
Diablo Canyon nuclear power plant. During the plant's construction, archeologists discovered a kitchen midden from prehistoric coastal dwellers who hunted deer and gathered shellfish. [Photo: Pacific Gas & Electric Co.]
The topic of when prehistoric people began using watercraft has gained intellectual momentum recently with the discovery of remains of a 14,000-year-old human settlement near the coast of Chile. The fact that this settlement predates any ever found in North America has thrown a wrench in the long-held theory that the Americas were colonized by people who walked across the Bering Strait, following an ice-free corridor into the interior of North America and onward into South America.
The discovery of the archeological site in Chile has forced archeologists to come up with an explanation for how people could have reached South America so early. One theory is that some people came not by foot but by boat. The early presence of Chendytes bones does not prove this theory but it is not inconsistent with it either, Jones said.
Pictures of the dig at Diablo Canyon circa 1968. [Photos: Roberta Greenwood of Greenwood and Assoc.]
In the case of the duck, its presence up until 4,000 years ago means it survived this climatic shift, implying that its extinction was more likely due to human exploitation. The archeological record that Jones is now studying corroborates this theory, too. There are progressively fewer Chendytes bones in midden layers through time, Jones said. In the oldest levels, dating back to about 10,000 years ago, 20 percent of the bones are from the duck. This diminishes in time until eventually the bones vanish completely from record. At this point, sea otter bones take their place, Jones said.
California Sea Grant originally funded Jones to examine the pattern of sea otter exploitation at the site.
Of particular interest is the relationship between sea otter exploitation (otters were hunted for their thick pelts and for food) and the prevalence and size of red abalone shells in refuse. The patterns of exploitation he is exploring, he hopes, will help modern-day managers have greater insights into the natural world and human influence on it.
"The discovery of the Chendytes bones was an unexpected and exciting find," Jones said. It will add a new dimension to his analysis of sea otter exploitation.
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